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The Brain as a Prediction Machine

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Over the last year, I’ve been reading a lot about Karl Friston and Andy Clark’s work on the concept of perception and action being mediated by a neurological schema centered on “predictive coding”, what Friston calls “active inference”, the “free energy principle”, and Bayesian inference in general as it applies to neuro-scientific models of perception, attention, and action.  Here’s a few links (Friston here; Clark here, here, and here) to some of their work as it is worth reading for those interested in neural modeling, information theory, and learning more about meta-theories pertaining to how the brain integrates and processes information.

I find it fascinating how this newer research and these concepts relate to and help to bring together some content from several of my previous blog posts, in particular, those that mention the concept of hierarchical neurological hardware and those that mention my own definition of knowledge “as recognized causal patterns that allow us to make successful predictions.”  For those that may be interested, here’s a list of posts I’ve made over the last few years that I think contain some relevant content (in chronological order).

The ideas formulated by Friston and expanded on by Clark center around the brain being (in large part) a prediction generating machine.  This fits in line with my own conclusions about what the brain seems to be doing when it’s acquiring knowledge over time (however limited my reading is on the subject).  Here’s an image of the basic predictive processing schema:

PPschema

The basic Predictive Processing schema (adapted from Lupyan and Clark (2014))

One key element in Friston and Clark’s work (among the work of some others) is the amalgamation of perception and action.  In this framework, perception itself is simply the result of the brain’s highest level predictions of incoming sensory data.  But also important in this framework is that prediction error minimization is accomplished through embodiment itself.  That is to say, their models posit that the brain not only tries to reduce prediction errors by updating its prediction models based on the actual incoming sensory information (with only the error feeding forward to update the models, similar to data compression schema), but the concept of active inference involves the minimization of prediction error through the use of motor outputs.  This could be taken to mean that motor outputs themselves are, in a sense, caused by the brain trying to reduce prediction errors pertaining to predicted sensory input — specifically sensory input that we would say stems from our desires and goals (e.g. desire to fulfill hunger, commuting to work, opening the car door, etc.).

To give a simple example of this model in action, let’s consider an apple resting on a table in front of me.  If I see the apple in front of me and I have a desire to grab it, my brain would not only predict what that apple looks like and how it is perceived over time (and how my arm looks while reaching for it), but it would also predict what it should feel like to reach for the apple.  So if I reach for it based on the somato-sensory prediction and there is some error in that prediction, corroborated by my visual cortex observing my arm moving in some wrong direction, the brain would respond by updating its models that predict what it should feel so that my arm starts moving in the proper direction.  This prediction error minimization is then fine-tuned as I get closer to the apple and can finally grab it.

This embodiment ingrained in the predictive processing models of Friston and Clark can also be well exemplified by the so-called “Outfielder’s Problem”.  In this problem, an outfielder is trying to catch a fly ball.  Now we know that outfielders are highly skilled at doing this rather effectively.  But if we ask the outfielder to merely stand still and watch a batted ball and predict where it will land, their accuracy is generally pretty bad.  So when we think about what strategy the brain takes to accomplish this when moving the body quickly, we begin to see the relevance of active inference and embodiment in the brain’s prediction schema.  The outfielder’s brain employs a brilliant strategy called “optical acceleration cancellation” (OAC).  Here, the well-trained outfielder sees the fly ball, and moves his or her body (while watching the ball) in order to cancel out any optical acceleration observed during the ball’s flight.  If they do this, then they will end up exactly where the ball was going to land, and then they’re able to catch it successfully.

We can imagine fine-grained examples of this active inference during everyday tasks, where I may simply be looking at a picture on my living room wall, and when my brain is predicting how it will look over the span of a few seconds, my head may slightly change its tilt, or direction, or my eyes may slowly move a fraction of a degree this way or that way, however imperceptible to me.  My brain in this case is predicting what the picture on the wall will look like over time and this prediction (according to my understanding of Clark) is identical to what we actually perceive.  One key thing to note here is that the prediction models are not simply updated based on the prediction error that is fed forward through the brain’s neurological hierarchies, but it is also getting some “help” from various motor movements to correct for the errors through action, rather than simply freezing all my muscles and updating the model itself (which may in fact be far less economical for the brain to do).

Another area of research that pertains to this framework, including ways of testing its validity, is that of evolutionary psychology and biology, where one would surmise (if these models are correct) that evolution likely provided our brains with certain hard-wired predictive models and our learning processes over time use these as starting points to produce innate reflexes (such as infant suckling to give a simple example) that allow us to survive long enough to update our models with actual new acquired information.  There are many different facets to this framework and I look forward to reading more about Friston and Clark’s work over the next few years.  I have a feeling that they have hit on something big, something that will help to answer a lot of questions about embodied cognition, perception, and even consciousness itself.

I encourage you to check out the links I provided pertaining to Friston and Clark’s work, to get a taste of the brilliant ideas they’ve been working on.

Conscious Realism & The Interface Theory of Perception

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A few months ago I was reading an interesting article in The Atlantic about Donald Hoffman’s Interface Theory of Perception.  As a person highly interested in consciousness studies, cognitive science, and the mind-body problem, I found the basic concepts of his theory quite fascinating.  What was most interesting to me was the counter-intuitive connection between evolution and perception that Hoffman has proposed.  Now it is certainly reasonable and intuitive to assume that evolutionary natural selection would favor perceptions that are closer to “the truth” or closer to the objective reality that exists independent of our minds, simply because of the idea that perceptions that are more accurate will be more likely to lead to survival than perceptions that are not accurate.  As an example, if I were to perceive lions as inert objects like trees, I would be more likely to be naturally selected against and eaten by a lion when compared to one who perceives lions as a mobile predator that could kill them.

While this is intuitive and reasonable to some degree, what Hoffman actually shows, using evolutionary game theory, is that with respect to organisms with comparable complexity, those with perceptions that are closer to reality are never going to be selected for nearly as much as those with perceptions that are tuned to fitness instead.  More so, truth in this case will be driven to extinction when it is up against perceptual models that are tuned to fitness.  That is to say, evolution will select for organisms that perceive the world in a way that is less accurate (in terms of the underlying reality) as long as the perception is tuned for survival benefits.  The bottom line is that given some specific level of complexity, it is more costly to process more information (costing more time and resources), and so if a “heuristic” method for perception can evolve instead, one that “hides” all the complex information underlying reality and instead provides us with a species-specific guide to adaptive behavior, that will always be the preferred choice.

To see this point more clearly, let’s consider an example.  Let’s imagine there’s an animal that regularly eats some kind of insect, such as a beetle, but it needs to eat a particular sized beetle or else it has a relatively high probability of eating the wrong kind of beetle (and we can assume that the “wrong” kind of beetle would be deadly to eat).  Now let’s imagine two possible types of evolved perception: it could have really accurate perceptions about the various sizes of beetles that it encounters so it can distinguish many different sizes from one another (and then choose the proper size range to eat), or it could evolve less accurate perceptions such that all beetles that are either too small or too large appear as indistinguishable from one another (maybe all the wrong-sized beetles whether too large or too small look like indistinguishable red-colored blobs) and perhaps all the beetles that are in the ideal size range for eating appear as green-colored blobs (that are again, indistinguishable from one another).  So the only discrimination in this latter case of perception is between red and green colored blobs.

Both types of perception would solve the problem of which beetles to eat or not eat, but the latter type (even if much less accurate) would bestow a fitness advantage over the former type, by allowing the animal to process much less information about the environment by not focusing on relatively useless information (like specific beetle size).  In this case, with beetle size as the only variable under consideration for survival, evolution would select for the organism that knows less total information about beetle size, as long as it knows what is most important about distinguishing the edible beetles from the poisonous beetles.  Now we can imagine that in some cases, the fitness function could align with the true structure of reality, but this is not what we ever expect to see generically in the world.  At best we may see some kind of overlap between the two but if there doesn’t have to be any then truth will go extinct.

Perception is Analogous to a Desktop Computer Interface

Hoffman analogizes this concept of a “perception interface” with the desktop interface of a personal computer.  When we see icons of folders on the desktop and drag one of those icons to the trash bin, we shouldn’t take that interface literally, because there isn’t literally a folder being moved to a literal trash bin but rather it is simply an interface that hides most if not all of what is really going on in the background — all those various diodes, resistors and transistors that are manipulated in order to modify stored information that is represented in binary code.

The desktop interface ultimately provides us with an easy and intuitive way of accomplishing these various information processing tasks because trying to do so in the most “truthful” way — by literally manually manipulating every diode, resistor, and transistor to accomplish the same task — would be far more cumbersome and less effective than using the interface.  Therefore the interface, by hiding this truth from us, allows us to “navigate” through that computational world with more fitness.  In this case, having more fitness simply means being able to accomplish information processing goals more easily, with less resources, etc.

Hoffman goes on to say that even though we shouldn’t take the desktop interface literally, obviously we should still take it seriously, because moving that folder to the trash bin can have direct implications on our lives, by potentially destroying months worth of valuable work on a manuscript that is contained in that folder.  Likewise we should take our perceptions seriously, even if we don’t take them literally.  We know that stepping in front of a moving train will likely end our conscious experience even if it is for causal reasons that we have no epistemic access to via our perception, given the species-specific “desktop interface” that evolution has endowed us with.

Relevance to the Mind-body Problem

The crucial point with this analogy is the fact that if our knowledge was confined to the desktop interface of the computer, we’d never be able to ascertain the underlying reality of the “computer”, because all that information that we don’t need to know about that underlying reality is hidden from us.  The same would apply to our perception, where it would be epistemically isolated from the underlying objective reality that exists.  I want to add to this point that even though it appears that we have found the underlying guts of our consciousness, i.e., the findings in neuroscience, it would be mistaken to think that this approach will conclusively answer the mind-body problem because the interface that we’ve used to discover our brains’ underlying neurobiology is still the “desktop” interface.

So while we may think we’ve found the underlying guts of “the computer”, this is far from certain, given the possibility of and support for this theory.  This may end up being the reason why many philosophers claim there is a “hard problem” of consciousness and one that can’t be solved.  It could be that we simply are stuck in the desktop interface and there’s no way to find out about the underlying reality that gives rise to that interface.  All we can do is maximize our knowledge of the interface itself and that would be our epistemic boundary.

Predictions of the Theory

Now if this was just a fancy idea put forward by Hoffman, that would be interesting in its own right, but the fact that it is supported by evolutionary game theory and genetic algorithm simulations shows that the theory is more than plausible.  Even better, the theory is actually a scientific theory (and not just a hypothesis), because it has made falsifiable predictions as well.  It predicts that “each species has its own interface (with some similarities between phylogenetically related species), almost surely no interface performs reconstructions (read the second link for more details on this), each interface is tailored to guide adaptive behavior in the relevant niche, much of the competition between and within species exploits strengths and limitations of interfaces, and such competition can lead to arms races between interfaces that critically influence their adaptive evolution.”  The theory predicts that interfaces are essential to understanding evolution and the competition between organisms, whereas the reconstruction theory makes such understanding impossible.  Thus, evidence of interfaces should be widespread throughout nature.

In his paper, he mentions the Jewel beetle as a case in point.  This beetle has a perceptual category, desirable females, which works well in its niche, and it uses it to choose larger females because they are the best mates.  According to the reconstructionist thesis, the male’s perception of desirable females should incorporate a statistical estimate of the true sizes of the most fertile females, but it doesn’t do this.  Instead, it has a category based on “bigger is better” and although this bestows a high fitness behavior for the male beetle in its evolutionary niche, if it comes into contact with a “stubbie” beer bottle, it falls into an infinite loop by being drawn to this supernormal stimuli since it is smooth, brown, and extremely large.  We can see that the “bigger is better” perceptual category relies on less information about the true nature of reality and instead chooses an “informational shortcut”.  The evidence of supernormal stimuli which have been found with many species further supports the theory and is evidence against the reconstructionist claim that perceptual categories estimate the statistical structure of the world.

More on Conscious Realism (Consciousness is all there is?)

This last link provided here shows the mathematical formalism of Hoffman’s conscious realist theory as proved by Chetan Prakash.  It contains a thorough explanation of the conscious realist theory (which goes above and beyond the interface theory of perception) and it also provides answers to common objections put forward by other scientists and philosophers on this theory.

Transcendental Argument For God’s Existence: A Critique

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Theist apologists and theologians have presented many arguments for the existence of God throughout history including the Ontological Argument, Cosmological Argument, Fine-Tuning Argument, the Argument from Morality, and many others — all of which having been refuted with various counter arguments.  I’ve written about a few of these arguments in the past (1, 2, 3), but one that I haven’t yet touched on is that of the Transcendental Argument for God (or simply TAG).  Not long ago I heard the Christian apologist Matt Slick conversing/debating with the well renowned atheist Matt Dillahunty on this topic and then I decided to look deeper into the argument as Slick presents it on his website.  I have found a number of problems with his argument, so I decided to iterate them in this post.

Slick’s basic argument goes as follows:

  1. The Laws of Logic exist.
    1. Law of Identity: Something (A) is what it is and is not what it is not (i.e. A is A and A is not not-A).
    2. Law of Non-contradiction: A cannot be both A and not-A, or in other words, something cannot be both true and false at the same time.
    3. Law of the Excluded Middle: Something must either be A or not-A without a middle ground, or in other words, something must be either true or false without a middle ground.
  2. The Laws of Logic are conceptual by nature — are not dependent on space, time, physical properties, or human nature.
  3. They are not the product of the physical universe (space, time, matter) because if the physical universe were to disappear, The Laws of Logic would still be true.
  4. The Laws of Logic are not the product of human minds because human minds are different — not absolute.
  5. But, since the Laws of Logic are always true everywhere and not dependent on human minds, it must be an absolute transcendent mind that is authoring them.  This mind is called God.
  6. Furthermore, if there are only two options to account for something, i.e., God and no God, and one of them is negated, then by default the other position is validated.
  7. Therefore, part of the argument is that the atheist position cannot account for the existence of The Laws of Logic from its worldview.
  8. Therefore God exists.

Concepts are Dependent on and the Product of Physical Brains

Let’s begin with number 2, 3, and 4 from above:

The Laws of Logic are conceptual by nature — are not dependent on space, time, physical properties, or human nature.  They are not the product of the physical universe (space, time, matter) because if the physical universe were to disappear, The Laws of Logic would still be true.  The Laws of Logic are not the product of human minds because human minds are different — not absolute.

Now I’d like to first mention that Matt Dillahunty actually rejected the first part of Slick’s premise here, as Dillahunty explained that while logic (the concept, our application of it, etc.) may in fact be conceptual in nature, the logical absolutes themselves (i.e. the laws of logic) which logic is based on are in fact neither conceptual nor physical.  My understanding of what Dillahunty was getting at here is that he was basically saying that just as the concept of an apple points to or refers to something real (i.e. a real apple) which is not equivalent to the concept of an apple, so also does the concept of the logical absolutes refer to something that is not the same as the concept itself.  However, what it points to, Dillahunty asserted, is something that isn’t physical either.  Therefore, the logical absolutes themselves are neither physical nor conceptual (as a result, Dillahunty later labeled “the essence” of the LOL as transcendent).  When Dillahunty was pressed by Slick to answer the question, “then what caused the LOL to exist?”, Dillahunty responded by saying that nothing caused them (or we have no reason to believe so) because they are transcendent and are thus not a product of anything physical nor conceptual.

If this is truly the case, then Dillahunty’s point here does undermine the validity of the logical structure of Slick’s argument, because Slick would then be beginning his argument by referencing the content and the truth of the logical absolutes themselves, and then later on switching to the concept of the LOL (i.e. their being conceptual in their nature, etc.).  For the purposes of this post, I’m going to simply accept Slick’s dichotomy that the logical absolutes (i.e. the laws of logic) are in fact either physical or conceptual by nature and then I will attempt to refute the argument anyway.  This way, if “conceptual or physical” is actually a true dichotomy (i.e. if there are no other options), despite the fact that Slick hasn’t proven this to be the case, his argument will be undermined anyway.  If Dillahunty is correct and “conceptual or physical” isn’t a true dichotomy, then even if my refutation here fails, Slick’s argument will still be logically invalid based on the points Dillahunty raised.

I will say however that I don’t think I agree with the point that Dillahunty made that the LOL are neither physical nor conceptual, and for a few reasons (not least of all because I am a physicalist).  My reasons for this will become more clear throughout the rest of this post, but in a nutshell, I hold that concepts are ultimately based on and thus are a subset of the physical, and the LOL would be no exception to this.  Beyond the issue of concepts, I believe that the LOL are physical in their nature for a number of other reasons as well which I’ll get to in a moment.

So why does Slick think that the LOL can’t be dependent on space?  Slick mentions in the expanded form of his argument that:

They do not stop being true dependent on location. If we travel a million light years in a direction, The Laws of Logic are still true.

Sure, the LOL don’t depend on a specific location in space, but that doesn’t mean that they aren’t dependent on space in general.  I would actually argue that concepts are abstractions that are dependent on the brains that create them based on those brains having recognized properties of space, time, and matter/energy.  That is to say that any concept such as the number 3 or the concept of redness is in fact dependent on a brain having recognized, for example, a quantity of discrete objects (which when generalized leads to the concept of numbers) or having recognized the color red in various objects (which when generalized leads to the concept of red or redness).  Since a quantity of discrete objects or a color must be located in some kind of space — even if three points on a one dimensional line (in the case of the number 3), or a two-dimensional red-colored plane (in the case of redness), then we can see that these concepts are ultimately dependent on space and matter/energy (of some kind).  Even if we say that concepts such as the color red or the number 3 do not literally exist in actual space nor are made of actual matter, they do have to exist in a mental space as mental objects, just as our conception of an apple floating in empty space doesn’t actually lie in space nor is made of matter, it nevertheless exists as a mental/perceptual representation of real space and real matter/energy that has been experienced by interaction with the physical universe.

Slick also mentions in the expanded form of his argument that the LOL can’t be dependent on time because:

They do not stop being true dependent on time. If we travel a billion years in the future or past, The Laws of Logic are still true.

Once again, sure, the LOL do not depend on a specific time, but rather they are dependent on time in general, because minds depend on time in order to have any experience of said concepts at all.  So not only are concepts only able to be formed by a brain that has created abstractions from physically interacting with space, matter, and energy within time (so far as we know), but the mind/concept-generating brain itself is also made of actual matter/energy, lying in real space, and operating/functioning within time.  So concepts are in fact not only dependent on space, time, and matter/energy (so far as we know), but are in fact also the product of space, time, and matter/energy, since it is only certain configurations of such that in fact produce a brain and the mind that results from said brain.  Thus, if the LOL are conceptual, then they are ultimately the product of and dependent on the physical.

Can Truth Exist Without Brains and a Universe?  Can Identities Exist Without a Universe?  I Don’t Think So…

Since Slick himself even claims that The Laws of Logic (LOL) are conceptual by nature, then that would mean that they are in fact also dependent on and the product of the physical universe, and more specifically are dependent on and the product of the human mind (or natural minds in general which are produced by a physical brain).  Slick goes on to say that the LOL can’t be dependent on the physical universe (which contains the brains needed to think or produce those concepts) because “…if the physical universe were to disappear, The Laws of Logic would still be true.”  It seems to me that without a physical universe, there wouldn’t be any “somethings” with any identities at all and so the Law of Identity which is the root of the other LOL wouldn’t apply to anything because there wouldn’t be anything and thus no existing identities.  Therefore, to say that the LOL are true sans a physical universe would be meaningless because identities themselves wouldn’t exist without a physical universe.  One might argue that abstract identities would still exist (like numbers or properties), but abstractions are products of a mind and thus need a brain to exist (so far as we know).  If one argued that supernatural identities would still exist without a physical universe, this would be nothing more than an ad hoc metaphysical assertion about the existence of the supernatural which carries a large burden of proof that can’t be (or at least hasn’t been) met.  Beyond that, if at least one of the supernatural identities was claimed to be God, this would also be begging the question.  This leads me to believe that the LOL are in fact a property of the physical universe (and appear to be a necessary one at that).

And if truth is itself just another concept, it too is dependent on minds and by extension the physical brains that produce those minds (as mentioned earlier).  In fact, the LOL seem to be required for any rational thought at all (hence why they are often referred to as the Laws of Thought), including the determination of any truth value at all.  So our ability to establish the truth value of the LOL (or the truth of anything for that matter) is also contingent on our presupposing the LOL in the first place.  So if there were no minds to presuppose the very LOL that are needed to establish its truth value, then could one say that they would be true anyway?  Wouldn’t this be analogous to saying that 1 + 1 = 2 would still be true even if numbers and addition (constructs of the mind) didn’t exist?  I’m just not sure that truth can exist in the absence of any minds and any physical universe.  I think that just as physical laws are descriptions of how the universe changes over time, these Laws of Thought are descriptions that underlie what our rational thought is based on, and thus how we arrive at the concept of truth at all.  If rational thought ceases to exist in the absence of a physical universe (since there are no longer any brains/minds), then the descriptions that underlie that rational thought (as well as their truth value) also cease to exist.

Can Two Different Things Have Something Fundamental in Common?

Slick then erroneously claims that the LOL can’t be the product of human minds because human minds are different and thus aren’t absolute, apparently not realizing that even though human minds are different from one another in many ways, they also have a lot fundamentally in common, such as how they process information and how they form concepts about the reality they interact with generally.  Even though our minds differ from one another in a number of ways, we nevertheless only have evidence to support the claim that human brains produce concepts and process information in the same general way at the most fundamental neurological level.  For example, the evidence suggests that the concept of the color red is based on the neurological processing of a certain range of wavelengths of electromagnetic radiation that have been absorbed by the eye’s retinal cells at some point in the past.  However, in Slick’s defense, I’ll admit that it could be the case that what I experience as the color red may be what you would call the color blue, and this would in fact suggest that concepts that we think we mutually understand are actually understood or experienced differently in a way that we can’t currently verify (since I can’t get in your mind and compare it to my own experience, and vice versa).

Nevertheless, just because our minds may experience color differently from one another or just because we may differ slightly in terms of what range of shades/tints of color we’d like to label as red, this does not mean that our brains/minds (or natural minds in general) are not responsible for producing the concept of red, nor does it mean that we don’t all produce that concept in the same general way.  The number 3 is perhaps a better example of a concept that is actually shared by humans in an absolute sense, because it is a concept that isn’t dependent on specific qualia (like the color red is).  The concept of the number 3 has a universal meaning in the human mind since it is derived from the generalization of a quantity of three discrete objects (which is independent of how any three specific objects are experienced in terms of their respective qualia).

Human Brains Have an Absolute Fundamental Neurology Which Encompasses the LOL

So I see no reason to believe that human minds differ at all in their conception of the LOL, especially if this is the foundation for rational thought (and thus any coherent concept formed by our brains).  In fact, I also believe that the evidence within the neurosciences suggests that the way the brain recognizes different patterns and thus forms different/unique concepts and such is dependent on the fact that the brain uses a hardware configuration schema that encompasses the logical absolutes.  In a previous post, my contention was that:

Additionally, if the brain’s wiring has evolved in order to see dimensions of difference in the world (unique sensory/perceptual patterns that is, such as quantity, colors, sounds, tastes, smells, etc.), then it would make sense that the brain can give any particular pattern an identity by having a unique schema of hardware or unique use of said hardware to perceive such a pattern and distinguish it from other patterns.  After the brain does this, the patterns are then arguably organized by the logical absolutes.  For example, if the hardware scheme or process used to detect a particular pattern “A” exists and all other patterns we perceive have or are given their own unique hardware-based identity (i.e. “not-A” a.k.a. B, C, D, etc.), then the brain would effectively be wired such that pattern “A” = pattern “A” (law of identity), any other pattern which we can call “not-A” does not equal pattern “A” (law of non-contradiction), and any pattern must either be “A” or some other pattern even if brand new, which we can also call “not-A” (law of the excluded middle).  So by the brain giving a pattern a physical identity (i.e. a specific type of hardware configuration in our brain that when activated, represents a detection of one specific pattern), our brains effectively produce the logical absolutes by nature of the brain’s innate wiring strategy which it uses to distinguish one pattern from another.  So although it may be true that there can’t be any patterns stored in the brain until after learning begins (through sensory experience), the fact that the DNA-mediated brain wiring strategy inherently involves eventually giving a particular learned pattern a unique neurological hardware identity to distinguish it from other stored patterns, suggests that the logical absolutes themselves are an innate and implicit property of how the brain stores recognized patterns.

So I believe that our brain produces and distinguishes these different “object” identities by having a neurological scheme that represents each perceived identity (each object) with a unique set of neurons that function in a unique way and thus which have their own unique identity.  Therefore, it would seem that the absolute nature of the LOL can easily be explained by how the brain naturally encompasses them through its fundamental hardware schema.  In other words, my contention is that our brain uses this wiring schema because it is the only way that it can be wired to make any discriminations at all and validly distinguish one identity from another in perception and thought, and this ability to discriminate various aspects of reality would be evolutionarily naturally-selected for based on the brain accurately modeling properties of the universe (in this case different identities/objects/causal-interactions existing) as it interacts with that environment via our sensory organs.  Which would imply that the existence of discrete identities is a property of the physical universe, and the LOL would simply be a description of what identities are.  This would explain why we see the LOL as absolute and fundamental and presuppose them.  Our brains simply encompass them in the most fundamental aspect of our neurology as it is a fundamental physical property of the universe that our brains model.

I believe that this is one of the reasons that Dillahunty and others believe that the LOL are transcendent (neither physical nor conceptual), because natural brains/minds are neurologically incapable of imagining a world existing without them.  The problem then only occurs because Dillahunty is abstracting a hypothetical non-physical world or mode of existence, yet doesn’t realize that he is unable to remove every physical property from any abstracted world or imagined mode of existence.  In this case, the physical property that he is unable to remove from his hypothetical non-physical world is his own neurological foundation, the very foundation that underlies all concepts (including that of existential identities) and which underlies all rational thought.  I may be incorrect about Dillahunty’s position here, but this is what I’ve inferred anyway based on what I’ve heard him say while conversing with Slick about this topic.

Human (Natural) Minds Can’t Account for the LOL, But Disembodied Minds Can?

Slick even goes on to say in point 5 that:

But, since the Laws of Logic are always true everywhere and not dependent on human minds, it must be an absolute transcendent mind that is authoring them.  This mind is called God.

We can see here that he concedes that the LOL is in fact the product of a mind, only he rejects the possibility that it could be a human mind (and by implication any kind of natural mind).  Rather, he insists that it must be a transcendent mind of some kind, which he calls God.  The problem with this conclusion is that we have no evidence or argument that demonstrates that minds can exist without physical brains existing in physical space within time.  To assume so is simply to beg the question.  Thus, he is throwing in an ontological/metaphysical assumption of substance dualism as well as that of disembodied minds, not only claiming that there must exist some kind of supernatural substance, but that this mysterious “non-physical” substance also has the ability to constitute a mind, and somehow do so without any dependence on time (even though mental function and thinking is itself a temporal process).  He assumes all of this of course without providing any explanation of how this mind could work even in principle without being made of any kind of stuff, without being located in any kind of space, and without existing in any kind of time.  As I’ve mentioned elsewhere concerning the ad hoc concept of disembodied minds:

…the only concept of a mind that makes any sense at all is that which involves the properties of causality, time, change, space, and material, because minds result from particular physical processes involving a very complex configuration of physical materials.  That is, minds appear to be necessarily complex in terms of their physical structure (i.e. brains), and so trying to conceive of a mind that doesn’t have any physical parts at all, let alone a complex arrangement of said parts, is simply absurd (let alone a mind that can function without time, change, space, etc.).  At best, we are left with an ad hoc, unintelligible combination of properties without any underlying machinery or mechanism.

In summary, I believe Slick has made several errors in his reasoning, with the most egregious being his unfounded assumption that natural minds aren’t capable of producing an absolute concept such as the LOL simply because natural minds have differences between one another (not realizing that all minds have fundamental commonalities), and also his argument’s reliance on the assumption that an ad hoc disembodied mind not only exists (whatever that could possibly mean) but that this mind can somehow account for the LOL in a way that natural minds can not, which is nothing more than an argument from ignorance, a logical fallacy.  He also insists that the Laws of Logic would be true without any physical universe, not realizing that the truth value of the Laws of Logic can only be determined by presupposing the Laws of Logic in the first place, which is circular, thus showing that the truth value of the Laws of Logic can’t be used to prove that they are metaphysically transcendent in any way (even if they actually happen to be metaphysically transcendent).  Lastly, without a physical universe of any kind, I don’t see how identities themselves can exist, and identities seem to be required in order for the LOL to be meaningful at all.

Darwin’s Big Idea May Be The Biggest Yet

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Back in 1859, Charles Darwin released his famous theory of evolution by natural selection whereby inherent variations in the individual members of some population of organisms under consideration would eventually lead to speciation events due to those variations producing a differential in survival and reproductive success and thus leading to the natural selection of some subset of organisms within that population.  As Darwin explained in his On The Origin of Species:

If during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometrical powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being’s own welfare, in the same way as so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. This principle of preservation, I have called, for the sake of brevity, Natural Selection.

While Darwin’s big idea completely transformed biology in terms of it providing (for the first time in history) an incredibly robust explanation for the origin of the diversity of life on this planet, his idea has since inspired other theories pertaining to perhaps the three largest mysteries that humans have ever explored: the origin of life itself (not just the diversity of life after it had begun, which was the intended scope of Darwin’s theory), the origin of the universe (most notably, why the universe is the way it is and not some other way), and also the origin of consciousness.

Origin of Life

In order to solve the first mystery (the origin of life itself), geologists, biologists, and biochemists are searching for plausible models of abiogenesis, whereby the general scheme of these models would involve chemical reactions (pertaining to geology) that would have begun to incorporate certain kinds of energetically favorable organic chemistries such that organic, self-replicating molecules eventually resulted.  Now, where Darwin’s idea of natural selection comes into play with life’s origin is in regard to the origin and evolution of these self-replicating molecules.  First of all, in order for any molecule at all to build up in concentration requires a set of conditions such that the reaction leading to the production of the molecule in question is more favorable than the reverse reaction where the product transforms back into the initial starting materials.  If merely one chemical reaction (out of a countless number of reactions occurring on the early earth) led to a self-replicating product, this would increasingly favor the production of that product, and thus self-replicating molecules themselves would be naturally selected for.  Once one of them was produced, there would have been a cascade effect of exponential growth, at least up to the limit set by the availability of the starting materials and energy sources present.

Now if we assume that at least some subset of these self-replicating molecules (if not all of them) had an imperfect fidelity in the copying process (which is highly likely) and/or underwent even a slight change after replication by reacting with other neighboring molecules (also likely), this would provide them with a means of mutation.  Mutations would inevitably lead to some molecules becoming more effective self-replicators than others, and then evolution through natural selection would take off, eventually leading to modern RNA/DNA.  So not only does Darwin’s big idea account for the evolution of diversity of life on this planet, but the basic underlying principle of natural selection would also account for the origin of self-replicating molecules in the first place, and subsequently the origin of RNA and DNA.

Origin of the Universe

Another grand idea that is gaining heavy traction in cosmology is that of inflationary cosmology, where this theory posits that the early universe underwent a period of rapid expansion, and due to quantum mechanical fluctuations in the microscopically sized inflationary region, seed universes would have resulted with each one having slightly different properties, one of which that would have expanded to be the universe that we live in.  Inflationary cosmology is currently heavily supported because it has led to a number of predictions, many of which that have already been confirmed by observation (it explains many large-scale features of our universe such as its homogeneity, isotropy, flatness, and other features).  What I find most interesting with inflationary theory is that it predicts the existence of a multiverse, whereby we are but one of an extremely large number of other universes (predicted to be on the order of 10^500, if not an infinite number), with each one having slightly different constants and so forth.

Once again, Darwin’s big idea, when applied to inflationary cosmology, would lead to the conclusion that our universe is the way it is because it was naturally selected to be that way.  The fact that its constants are within a very narrow range such that matter can even form, would make perfect sense, because even if an infinite number of universes exist with different constants, we would only expect to find ourselves in one that has the constants within the necessary range in order for matter, let alone life to exist.  So any universe that harbors matter, let alone life, would be naturally selected for against all the other universes that didn’t have the right properties to do so, including for example, universes that had too high or too low of a cosmological constant (such as those that would have instantly collapsed into a Big Crunch or expanded into a heat death far too quickly for any matter or life to have formed), or even universes that didn’t have the proper strong nuclear force to hold atomic nuclei together, or any other number of combinations that wouldn’t work.  So any universe that contains intelligent life capable of even asking the question of their origins, must necessarily have its properties within the required range (often referred to as the anthropic principle).

After our universe formed, the same principle would also apply to each galaxy and each solar system within those galaxies, whereby because variations exist in each galaxy and within each substituent solar system (differential properties analogous to different genes in a gene pool), then only those that have an acceptable range of conditions are capable of harboring life.  With over 10^22 stars in the observable universe (an unfathomably large number), and billions of years to evolve different conditions within each solar system surrounding those many stars, it isn’t surprising that eventually the temperature and other conditions would be acceptable for liquid water and organic chemistries to occur in many of those solar systems.  Even if there was only one life permitting planet per galaxy (on average), that would add up to over 100 billion life permitting planets in the observable universe alone (with many orders of magnitude more life permitting planets in the non-observable universe).  So given enough time, and given some mechanism of variation (in this case, differences in star composition and dynamics), natural selection in a sense can also account for the evolution of some solar systems that do in fact have life permitting conditions in a universe such as our own.

Origin of Consciousness

The last significant mystery I’d like to discuss involves the origin of consciousness.  While there are many current theories pertaining to different aspects of consciousness, and while there has been much research performed in the neurosciences, cognitive sciences, psychology, etc., pertaining to how the brain works and how it correlates to various aspects of the mind and consciousness, the brain sciences (though neuroscience in particular) are in their relative infancy and so there are still many questions that haven’t been answered yet.  One promising theory that has already been shown to account for many aspects of consciousness is Gerald Edelman’s theory of neuronal group selection (NGS) otherwise known as neural Darwinism (ND), which is a large scale theory of brain function.  As one might expect from the name, the mechanism of natural selection is integral to this theory.  In ND, the basic idea consists of three parts as read on the Wiki:

  1. Anatomical connectivity in the brain occurs via selective mechanochemical events that take place epigenetically during development.  This creates a diverse primary neurological repertoire by differential reproduction.
  2. Once structural diversity is established anatomically, a second selective process occurs during postnatal behavioral experience through epigenetic modifications in the strength of synaptic connections between neuronal groups.  This creates a diverse secondary repertoire by differential amplification.
  3. Re-entrant signaling between neuronal groups allows for spatiotemporal continuity in response to real-world interactions.  Edelman argues that thalamocortical and corticocortical re-entrant signaling are critical to generating and maintaining conscious states in mammals.

In a nutshell, the basic differentiated structure of the brain that forms in early development is accomplished through cellular proliferation, migration, distribution, and branching processes that involve selection processes operating on random differences in the adhesion molecules that these processes use to bind one neuronal cell to another.  These crude selection processes result in a rough initial configuration that is for the most part fixed.  However, because there are a diverse number of sets of different hierarchical arrangements of neurons in various neuronal groups, there are bound to be functionally equivalent groups of neurons that are not equivalent in structure, but are all capable of responding to the same types of sensory input.  Because some of these groups should in theory be better than others at responding to some particular type of sensory stimuli, this creates a form of neuronal/synaptic competition in the brain, whereby those groups of neurons that happen to have the best synaptic efficiency for the stimuli in question are naturally selected over the others.  This in turn leads to an increased probability that the same network will respond to similar or identical signals in the future.  Each time this occurs, synaptic strengths increase in the most efficient networks for each particular type of stimuli, and this would account for a relatively quick level of neural plasticity in the brain.

The last aspect of the theory involves what Edelman called re-entrant signaling whereby a sampling of the stimuli from functionally different groups of neurons occurring at the same time leads to a form of self-organizing intelligence.  This would provide a means for explaining how we experience spatiotemporal consistency in our experience of sensory stimuli.  Basically, we would have functionally different parts of the brain, such as various maps in the visual centers that pertain to color versus others that pertain to orientation or shape, that would effectively amalgamate the two (previously segregated) regions such that they can function in parallel and thus correlate with one another producing an amalgamation of the two types of neural maps.  Once this re-entrant signaling is accomplished between higher order or higher complexity maps in the brain, such as those pertaining to value-dependent memory storage centers, language centers, and perhaps back to various sensory cortical regions, this would create an even richer level of synchronization, possibly leading to consciousness (according to the theory).  In all of the aspects of the theory, the natural selection of differentiated neuronal structures, synaptic connections and strengths and eventually that of larger re-entrant connections would be responsible for creating the parallel and correlated processes in the brain believed to be required for consciousness.  There’s been an increasing amount of support for this theory, and more evidence continues to accumulate in support of it.  In any case, it is a brilliant idea and one with a lot of promise in potentially explaining one of the most fundamental aspects of our existence.

Darwin’s Big Idea May Be the Biggest Yet

In my opinion, Darwin’s theory of evolution through natural selection was perhaps the most profound theory ever discovered.  I’d even say that it beats Einstein’s theory of Relativity because of its massive explanatory scope and carryover to other disciplines, such as cosmology, neuroscience, and even the immune system (see Edelman’s Nobel work on the immune system, where he showed how the immune system works through natural selection as well, as opposed to some type of re-programming/learning).  Based on the basic idea of natural selection, we have been able to provide a number of robust explanations pertaining to many aspects of why the universe is likely to be the way it is, how life likely began, how it evolved afterward, and it may possibly be the answer to how life eventually evolved brains capable of being conscious.  It is truly one of the most fascinating principles I’ve ever learned about and I’m honestly awe struck by its beauty, simplicity, and explanatory power.

Substance Dualism, Interactionism, & Occam’s razor

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Recently I got into a discussion with Gordon Hawkes on A Philosopher’s Take about the arguments and objections for substance dualism, that is, the position that there are actually two ontological substances that exist in the world: physical substances and mental (or non-physical) substances.  Here’s the link to part 1, and part 2 of that author’s post series (I recommend taking a look at this group blog and see what he and others have written over there on various interesting topics).  Many dualists would identify or liken this supposed second substance as a soul or the like, but I’m not going to delve into that particular detail within this post.  I’d prefer to focus on the basics of the arguments presented rather than those kinds of details.  Before I dive into the topic, I want to mention that Hawkes was by no means making an argument for substance dualism, but rather he was merely pointing out some flaws in common arguments against substance dualism.  Now that that’s been said, I’m going to get to the heart of the topic, but I will also be providing evidence and arguments against substance dualism.  The primary point raised in the first part of that series was the fact that just because neuroscience is continuously finding correlations between particular physical brain states and particular mental states, this doesn’t mean that these empirical findings show that dualism is necessarily false — since some forms of dualism seem to be entirely compatible with these empirical findings (e.g. interactionist dualism).  So the question ultimately boils down to whether or not mental processes are identical with, or metaphysically supervenient upon, the physical processes of the brain (if so, then substance dualism is necessarily false).

Hawkes talks about how the argument from neuroscience (as it is sometimes referred to) is fallacious because it is based on the mistaken belief that correlation (between mental states and brain states) is equivalent with identity or supervenience of mental and physical states.  Since this isn’t the case, then one can’t rationally use the neurological correlation to disprove (all forms of) substance dualism.  While I agree with this, that is, that the argument from neuroscience can’t be used to disprove (all forms of) substance dualism, it is nevertheless strong evidence that a physical foundation exists for the mind and it also provides evidence against all forms of substance dualism that posit that the mind can exist independently of the physical brain.  At the very least, it shows that the prior probability of minds existing without brains is highly unlikely.  This would seem to suggest that any supposed mental substance is necessarily dependent on a physical substance (so disembodied minds would be out of the question for the minimal substance dualist position).  Even more damning for substance dualists though, is the fact that since the argument from neuroscience suggests that minds can’t exist without physical brains, this would mean that prior to brains evolving in any living organisms within our universe, at some point in the past there weren’t any minds at all.  This in turn would suggest that the second substance posited by dualists isn’t at all conserved like the physical substances we know about are conserved (as per the Law of Conservation of Mass and Energy).  Rather, this second substance would have presumably had to have come into existence ex nihilo once some subset of the universe’s physical substances took on a particular configuration (i.e. living organisms that eventually evolved a brain complex enough to afford mental experiences/consciousness/properties).  Once all the brains in the universe disappear in the future (after the heat death of the universe guarantees such a fate), then this second substance will once again disappear from our universe.

The only way around this (as far as I can tell) is to posit that the supposed mental substance had always existed and/or will always continue to exist, but in an entirely undetectable way somehow detached from any physical substance (which is a position that seems hardly defensible given the correlation argument from neuroscience).  Since our prior probabilities of any hypothesis are based on all our background knowledge, and since the only substance we can be sure of exists (a physical substance) has been shown to consistently abide by conservation laws (within the constraints of general relativity and quantum mechanics), it is more plausible that any other ontological substance would likewise be conserved rather than not conserved.  If we had evidence to the contrary, that would change the overall consequent probability, but without such evidence, we only have data points from one ontological substance, and it appears to follow conservation laws.  For this reason alone, it is less likely that a second substance exists at all, if it isn’t itself conserved as that of the physical.

Beyond that, the argument from neuroscience also provides at least some evidence against interactionism (the idea that the mind and brain can causally interact with each other in both causal directions), and interactionism is something that substance dualists would likely need in order to have any reasonable defense of their position at all.  To see why this is true, one need only recognize the fact that the correlates of consciousness found within neuroscience consist of instances of physical brain activity that are observed prior to the person’s conscious awareness of any experience, intentions, or willed actions produced by said brain activity.  For example, studies have shown that when a person makes a conscious decision to do something (say, to press one of two possible buttons placed in front of them), there are neurological patterns that can be detected prior to their awareness of having made a decision and so these patterns can be used to correctly predict which choice the person will make even before they do!  I would say that this is definitely evidence against interactionism, because we have yet to find any cases of mental experiences occurring prior to the brain activity that is correlated with it.  We’ve only found evidence of brain activity preceding mental experiences, never the other way around.  If the mind was made from a different substance, existing independently of the physical brain (even if correlated with it), and able to causally interact with the physical brain, then it seems reasonable to expect that we should be able to detect and confirm instances of mental processes/experiences occurring prior to correlated changes in physical brain states.  Since this hasn’t been found yet in the plethora of brain studies performed thus far, the prior probability of interactionism being true is exceedingly low.  Additionally, the conservation of mass and energy that we observe (as well as the laws of physics in general) in our universe also challenges the possibility of any means of causal energy transfer between a mind to a brain or vice versa.  For the only means of causal interaction we’ve observed thus far in our universe is by way of energy/momentum transfer from one physical particle/system to another.  If a mind is non-physical, then by what means can it interact at all with a brain or vice versa?

The second part of the post series from Hawkes talked about Occam’s razor and how it’s been applied in arguments against dualism.  Hawkes argues that even though one ontological substance is less complex and otherwise preferred over two substances (when all else is equal), Occam’s razor apparently isn’t applicable in this case because physicalism has been unable to adequately address what we call a mind, mental properties, etc.  My rebuttal to this point is that dualism doesn’t adequately address what we call a mind, mental properties, etc., either.  In fact it offers no additional explanatory power than physicalism does because nobody has proposed how it could do so.  That is, nobody has yet demonstrated (as far as I know) what any possible mechanisms would be for this new substance to instantiate a mind, how this non-physical substance could possibly interact with the physical brain, etc.  Rather it seems to have been posited out of an argument from ignorance and incredulity, which is a logical fallacy.  Since physicalism hasn’t yet provided a satisfactory explanation for what some call the mind and mental properties, it is therefore supposed by dualists that a second ontological substance must exist that does explain it or account for it adequately.

Unfortunately, because of the lack of any proposed mechanism for the second substance to adequately account for the phenomena, one could simply replace the term “second substance” with “magic” and be on the same epistemic footing.  It is therefore an argument from ignorance to presume that a second substance exists, for the sole reason that nobody has yet demonstrated how the first substance can fully explain what we call mind and mental phenomena.  Just as we’ve seen throughout history where an unknown phenomena is attributed to magic or the supernatural and later found to be accounted for by a physical explanation, this means that the prior probability that this will also be the case for the phenomena of the mind and mental properties is extraordinarily high.  As a result, I think that Occam’s razor is applicable in this case, because I believe it is always applicable to an argument from ignorance that’s compared to an (even incomplete) argument from evidence.  Since physicalism accounts for many aspects of mental phenomena (such as the neuroscience correlations, etc.), dualism needs to be supported by at least some proposed mechanism (that is falsifiable) in order to nullify the application of Occam’s razor.

Those are my thoughts on the topic for now.  I did think that Hawkes made some valid points in his post series — such as the fact that correlation doesn’t equal identity or supervenience and also the fact that Occam’s razor is only applicable under particular circumstances (such as when both hypotheses explain the phenomena equally, good or bad, with one containing a more superfluous ontology).  However, I think that overall the arguments and evidence against substance dualism are strong enough to eliminate any reasonable justification for supposing that dualism is true (not that Hawkes was defending dualism as he made clear at the beginning of his post) and I also believe that both physicalism and dualism explain the phenomena equally well such that Occam’s razor is applicable (since dualism doesn’t seem to add any explanatory power to that already provided by physicalism).  So even though correlation doesn’t equal identity or supervenience, the arguments and evidence from neuroscience and physics challenge the possibility of any interactionism between the physical and supposed non-physical substance, and it challenges the existence of the second substance in general (due to it’s apparent lack of conservation over time among other reasons).

The Origin and Evolution of Life: Part II

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Even though life appears to be favorable in terms of the second law of thermodynamics (as explained in part one of this post), there have still been very important questions left unanswered regarding the origin of life including what mechanisms or platforms it could have used to get itself going initially.  This can be summarized by a “which came first, the chicken or the egg” dilemma, where biologists have wondered whether metabolism came first or if instead it was self-replicating molecules like RNA that came first.

On the one hand, some have argued that since metabolism is dependent on proteins and enzymes and the cell membrane itself, that it would require either RNA or DNA to code for those proteins needed for metabolism, thus implying that RNA or DNA would have to originate before metabolism could begin.  On the other hand, even the generation and replication of RNA or DNA requires a catalytic substrate of some kind and this is usually accomplished with proteins along with metabolic driving forces to accomplish those polymerization reactions, and this would seem to imply that metabolism along with some enzymes would be needed to drive the polymerization of RNA or DNA.  So biologists we’re left with quite a conundrum.  This was partially resolved when several decades ago, it was realized that RNA has the ability to not only act as a means of storing genetic information just like DNA, but it also has the additional ability of catalyzing chemical reactions just like an enzyme protein can.  Thus, it is feasible that RNA could act as both an information storage molecule as well as an enzyme.  While this helps to solve the problem if RNA began to self-replicate itself and evolve over time, the problem still remains of how the first molecules of RNA formed, because it seems that some kind of non-RNA metabolic catalyst would be needed to drive this initial polymerization.  Which brings us back to needing some kind of catalytic metabolism to drive these initial reactions.

These RNA polymerization reactions may have spontaneously formed on their own (or evolved from earlier self-replicating molecules that predated RNA), but the current models of how the early pre-biotic earth would have been around four billion years ago seem to suggest that there would have been too many destructive chemical reactions that would have suppressed the accumulation of any RNA and would have likely suppressed other self-replicating molecules as well.  What seems to be needed then is some kind of a catalyst that could create them quickly enough such that they would be able to accumulate in spite of any destructive reactions present, and/or some kind of physical barrier (like a cell wall) that protects the RNA or other self-replicating polymers so that they don’t interact with those destructive processes.

One possible solution to this puzzle that has been developing over the last several years involves alkaline hydrothermal vents.  We actually didn’t know that these kinds of vents existed until the year 2000 when they were discovered on a National Science Foundation expedition in the mid-Atlantic.  Then a few years later they were studied more closely to see what kinds of chemistries were involved with these kinds of vents.  Unlike the more well-known “black smoker” vents (which were discovered in the 1970’s), these alkaline hydrothermal vents have several properties that would have been hospitable to the emergence of life back during the Hadeon eon (between 4.6 and 4 billion years ago).

The ocean water during the Hadeon eon would have been much more acidic due to the higher concentrations of carbon dioxide (thus forming carbonic acid), and this acidic ocean water would have mixed with the hydrogen-rich alkaline water found within the vents, and this would have formed a natural proton gradient within the naturally formed pores of these rocks.  Also, electron transfer would have likely occurred when the hydrogen and methane-rich vent fluid contacted the carbon dioxide-rich ocean water, thus generating an electrical gradient.  This is already very intriguing because all living cells ultimately derive their metabolic driving forces from proton gradients or more generally from the flow of some kind of positive charge carrier and/or electrons.  Since the rock found in these vents undergoes a process called surpentization, which spreads the rock apart into various small channels and pockets, many different kinds of pores form in the rocks, and some of them would have been very thin-walled membranes separating the acidic ocean water from the alkaline hydrogen.  This would have facilitated the required semi-permeable barrier that modern cells have which we expect the earliest proto-cells to also have, and it would have provided the necessary source of energy to power various chemical reactions.

Additionally, these vents would have also provided a source of minerals (namely green rust and molybdenum) which likely would have behaved as enzymes, catalyzing reactions as various chemicals came into contact with them.  The green rust could have allowed the use of the proton gradient to generate molecules that contained phosphate, which could have stored the energy produced from the gradient — similar to how all living systems that we know of store their energy in ATP (Adenosine Tri-Phosphate).  The molybdenum on the other hand would have assisted in electron transfer through those membranes.

So this theory provides a very plausible way for catalytic metabolism as well as proto-cellular membrane formation to have resulted from natural geological processes.  These proto-cells would then likely have begun concentrating simple organic molecules formed from the reaction of CO2 and H2 with all the enzyme-like minerals that were present.  These molecules could then react with one another to polymerize and form larger and more complex molecules including eventually nucleotides and amino acids.  One promising clue that supports this theory is the fact that every living system on earth is known to share a common metabolic system, known as the citric acid cycle or Kreb’s cycle, where it operates in the forward direction for aerobic organisms and in the reverse direction for anaerobic organisms.  Since this cycle consists of only 11 molecules, and since all biological components and molecules that we know of in any species have been made by some number or combination of these 11 fundamental building blocks, scientists are trying to test (among other things) whether or not they can mimic these alkaline hydrothermal vent conditions along with the acidic ocean water that would have been present in the Hadrean era and see if it will precipitate some or all of these molecules.  If they can, it will show that this theory is more than plausible to account for the origin of life.

Once these basic organic molecules were generated, eventually proteins would have been able to form, some of which that could have made their way to the membrane surface of the pores and acted as pumps to direct the natural proton gradient to do useful work.  Once those proteins evolved further, it would have been possible and advantageous for the membranes to become less permeable so that the gradient could be highly focused on the pump channels on the membrane of these proto-cells.  The membrane could have begun to change into one made from lipids produced from the metabolic reactions, and we already know that lipids readily form micelles or small closed spherical structures once they aggregate in aqueous conditions.  As this occurred, the proto-cells would no longer have been trapped in the porous rock, but would have eventually been able to slowly migrate away from the vents altogether, eventually forming the phospholipid bi-layer cell membranes that we see in modern cells.  Once this got started, self-replicating molecules and the rest of the evolution of the cell would have underwent natural selection as per the Darwinian evolution that most of us are familiar with.

As per the earlier discussion regarding life serving as entropy engines and energy dissipation channels, this self-replication would have been favored thermodynamically as well because replicating those entropy engines and the energy dissipation channels means that they will only become more effective at doing so.  Thus, we can tie this all together, where natural geological processes would have allowed for the required metabolism to form, thus powering organic molecular synthesis and polymerization, and all of these processes serving to increase entropy and maximize energy dissipation.  All that was needed for this to initiate was a planet that had common minerals, water, and CO2, and the natural geological processes can do the rest of the work.  These kinds of planets actually seem to be fairly common in our galaxy, with estimates ranging in the billions, thus potentially harboring life (or where it is just a matter of time before it initiates and evolves if it hasn’t already).  While there is still a lot of work to be done to confirm the validity of these models and to try to find ways of testing them vigorously, we are getting relatively close to solving the puzzle of how life originated, why it is the way it is, and how we can better search for it in other parts of the universe.

Neurological Configuration & the Prospects of an Innate Ontology

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After a brief discussion on another blog pertaining to whether or not humans possess some kind of an innate ontology or other forms of what I would call innate knowledge, I decided to expand on my reply to that blog post.

While I agree that at least most of our knowledge is acquired through learning, specifically through the acquisition and use of memorized patterns of perception (as this is generally how I would define knowledge), I also believe that there are at least some innate forms of knowledge, including some that would likely result from certain aspects of our brain’s innate neurological configuration and implementation strategy.  This proposed form of innate knowledge would seem to bestow a foundation for later acquiring the bulk of our knowledge that is accomplished through learning.  This foundation would perhaps be best described as a fundamental scaffold of our ontology and thus an innate aspect that our continually developing ontology is based on.

My basic contention is that the hierarchical configuration of neuronal connections in our brains is highly analogous to the hierarchical relationships utilized to produce our conceptualization of reality.  In order for us to make sense of the world, our brains seem to fracture reality into many discrete elements, properties, concepts, propositions, etc., which are all connected to each other through various causal relationships or what some might call semantic hierarchies.  So it seems plausible if not likely that the brain is accomplishing a fundamental aspect of our ontology by our utilizing an innate hardware schema that involves neurological branching.

As the evidence in the neurosciences suggests, it certainly appears that our acquisition of knowledge through learning what those discrete elements, properties, concepts, propositions, etc., are, involves synaptogenesis followed by pruning, modifying, and reshaping a hierarchical neurological configuration, in order to end up with a more specific hierarchical neurological arrangement, and one that more accurately correlates with the reality we are interacting with and learning about through our sensory organs.  Since the specific arrangement that eventually forms couldn’t have been entirely coded for in our DNA (due to it’s extremely high level of complexity and information density), it ultimately had to be fine-tuned to this level of complexity after it’s initial pre-sensory configuration developed.  Nevertheless, the DNA sequences that were naturally selected for to produce the highly capable brains of human beings (as opposed to the DNA that guides the formation of the brain of a much less intelligent animal), clearly have encoded increasingly more effective hardware implementation strategies than our evolutionary ancestors.  These naturally selected neurological strategies seem to control what particular types of causal patterns the brain is theoretically capable of recognizing (including some upper limit of complexity), and they also seem to control how the brain stores and organizes these patterns for later use.  So overall, my contention is that these naturally selected strategies in themselves are a type of knowledge, because they seem to provide the very foundation for our initial ontology.

Based on my understanding, after many of the initial activity-independent mechanisms for neural development have occurred in some region of the developing brain such as cellular differentiation, cellular migration, axon guidance, and some amount of synapse formation, then the activity-dependent mechanisms for neuronal development (such as neural activity caused by the sensory organs in the process of learning), finally begin to modify those synapses and axons into a new hierarchical arrangement.  It is especially worth noting that even though much of the synapse formation during neural development is mediated by activity-dependent mechanisms, such as the aforementioned neural activity produced by the sensory organs during perceptual development and learning, there is also spontaneous neural activity forming many of these synapses even before any sensory input is present, thus contributing to the innate neurological configuration (i.e. that which is formed before any sensation or learning has occurred).

Thus, the subsequent hierarchy formed through neural/sensory stimulation via learning appears to begin from a parent hierarchical starting point based on neural developmental processes that are coded for in our DNA as well as synaptogenic mechanisms involving spontaneous pre-sensory neural activity.  So our brain’s innate (i.e. pre-sensory) configuration likely contributes to our making sense of the world by providing a starting point that reflects the fundamental hierarchical nature of reality that all subsequent knowledge is built off of.  In other words, it seems that if our mature conceptualization of reality involves a very specific type of hierarchy, then an innate/pre-sensory hierarchical schema of neurons would be a plausible if not expected physical foundation for it (see Edelman’s Theory of Neuronal Group Selection within this link for more empirical support of these points).

Additionally, if the brain’s wiring has evolved in order to see dimensions of difference in the world (unique sensory/perceptual patterns that is, such as quantity, colors, sounds, tastes, smells, etc.), then it would make sense that the brain can give any particular pattern an identity by having a unique schema of hardware or unique use of said hardware to perceive such a pattern and distinguish it from other patterns.  After the brain does this, the patterns are then arguably organized by the logical absolutes.  For example, if the hardware scheme or process used to detect a particular pattern “A” exists and all other patterns we perceive have or are given their own unique hardware-based identity (i.e. “not-A” a.k.a. B, C, D, etc.), then the brain would effectively be wired such that pattern “A” = pattern “A” (law of identity), any other pattern which we can call “not-A” does not equal pattern “A” (law of non-contradiction), and any pattern must either be “A” or some other pattern even if brand new, which we can also call “not-A” (law of the excluded middle).  So by the brain giving a pattern a physical identity (i.e. a specific type of hardware configuration in our brain that when activated, represents a detection of one specific pattern), our brains effectively produce the logical absolutes by nature of the brain’s innate wiring strategy which it uses to distinguish one pattern from another.  So although it may be true that there can’t be any patterns stored in the brain until after learning begins (through sensory experience), the fact that the DNA-mediated brain wiring strategy inherently involves eventually giving a particular learned pattern a unique neurological hardware identity to distinguish it from other stored patterns, suggests that the logical absolutes themselves are an innate and implicit property of how the brain stores recognized patterns.

In short, if it is true that any and all forms of reasoning as well as the ability to accumulate knowledge simply requires logic and the recognition of causal patterns, and if the brain’s innate neurological configuration schema provides the starting foundation for both, then it would seem reasonable to conclude that the brain has at least some types of innate knowledge.