Is it circular to argue that evolution supports realism?

[Positor]

It is sometimes argued that the world in itself must bear a close resemblance to the world of appearance, because otherwise humans would not have been able to survive and evolve; we must be fitted to our real environment. It is said that Kant was therefore wrong to argue that things-in-themselves are unknowable, and that he would probably have changed his mind if he had lived to read Darwin's theory.

However, the fact that there is such a thing as evolution at all is something we learn through sense experience (reading and listening), just like any other fact such as that there are mountains, or that ice is cold, or that Julius Caesar ruled Rome. The truth of evolution is therefore no more certain than any of these other 'obvious' truths, including the existence of the entire world. It thus seems to beg the question if we assume the reality of evolution as evidence of the reality of the world. If our direct sense experience is insufficient to convince us of the external reality of everyday objects (i.e. if sense experience is considered a 'weak link' in the chain of inference), why should our apparent knowledge of evolution (which we learn about via the same 'weak link') provide a firmer basis?

1. It is possible that things in the world of appearance do not correspond to any things-in-themselves (because the former are mediated by the structure of our mind).

2. Evolution is a thing in the world of appearance.

3. Therefore, it is possible that evolution does not correspond to any thing-in-itself.

4. Therefore, things-in-themselves need not be such as to enable humans to survive over an extended period.

5. Therefore, things-in-themselves may be completely different from things in the world of appearance. Perhaps, for example, I am a brain in a vat, or (per Dave Oblad) part of a mathematical formula (one of an infinite number of such formulae, covering all possible states of affairs).

[owleye]

As the argument referred to by Positor is one I endorse, it is important that I respond to it. And indeed, I've had the very thoughts he (assumed gender) is expanding on and so I'm at least aware of the problem he is addressing. For that I'm grateful that it gives me another opportunity to think about it more.

As it's late and I'm a bit tired, I'll only attempt to sketch out an argument.

Note that my argument will differ extensively from the argument presented by Positor so it doesn't count as a rebuttal argument to his. I do so only because I'm a target of his argument and wish to gather my thoughts. Perhaps if I'm not yet exhausted, I'll attempt to challenge his argument. If I don't now I'll do so in another post.

P1. Darwinian evolution is the true description of life's history.

P2. Humans belong to that history, they having evolved within an evolutionary chain of descent.

P3. Humans have minds that are subject to evolutionary forces and have adapted to their environment in ways that differentiate them from other living things though in the chain of their descent have properties that are carried forward from their ancestry.

P4. The minds of humans evolved from those of their ancestry.

P5. Perception is a property of the mind.

P6. Perception involves capturing information from the environment and processing it in such a way that a world is presented to humans (in the form of a representation or a set of representations each of which is associated with a sense organ) that are more or less faithful to the information in the environment itself.

(I base this premise on the biological success of the adaption of perception to its environment. If it wasn't faithful, it would be weeded out by natural selection.)

P7. The environment in which living things evolve precedes its evolution.

P8. Humans exist.

Conclusion: The objects represented in perception are real in so far as their information content is faithful to that which the representation is a representation of.

A couple of points are worth mentioning. I recall an idealist coming to this board (who stayed only briefly) making a case for idealism, much like that of Berkeley, I think. In responding to the position he crafted, I asked him how he would take into consideration evolutionary theory in so far as it requires an evolutionary past in which humans themselves had no existence. He gave it some thought and concluded that perhaps as the OP hints at, evolutionary theory isn't true. Another possible route, also considered by the OP, is that though evolution may be true, it's possible that, as with Leibniz's idealism, it, and everything that science describes only exists in a phenomenal setting. What's real is merely how our mind organizes itself. As such, they would reject P3. The human mind is responsible for the organization which brought about life itself and its history.

Well, I accept that idealism may be a possible ontology, but I'm much more comfortable with the argument I've made. (My argument undoubtedly requires a few missing premises filled in to make it rigorous.)

Before I retire let me add a couple of thoughts on Positor's argument as presented.

1. The correspondence between what appears and what the appearance is an appearance of ought not to be in accordance with the imaging of the world as it is represented in perception to the same in the the actual world. Rather the correspondence is in respect to the information in the actual world to the information in the representation.

2. The correspondence is restricted to the spatial and temporal details in accordance with the relationship between the organism (i.e. us) and its (our) environment. As such, we are middle-sized creatures who have a biological relationship to a middle-sized environment. We don't see tiny objects (except as they are made middle-sized by a micro-scope. We don't see far away objects except as they are brought to middle-size by telescopes.

3. The correspondence measure is that of sufficiently accurate, where that sufficiency is measured in accordance with how dependent humans are on these representations in being biologically successful. (Note some animals need extraordinary eyesight, while others rely on other senses. We probably are less dependent on perception than our ancestors because we compensate by having more intelligence respecting our environment.

4. The concept of a 'thing in itself' is one that was au currant during the enlightenment, especially within Germany. I think it only makes sense in an ontology which thinks of the mind or soul as that entity which exists inside of its surrounding body, in kind of a dualist fashion. Kant, of course, uses this term, in the context of a noumenal world, which in my view he later abandoned, notwithstanding that the term remained kind of an albatross hanging over his head for centuries, perhaps even now. I'd prefer to shorten it to "thing itself' whereby the thing-itself can be known at least with respect to its exhibited properties.

James

[yadayada]

It is sometimes argued that the world in itself must bear a close resemblance to the world of appearance, because otherwise humans would not have been able to survive and evolve; we must be fitted to our real environment.

This appears to me to be based on the definition of evolution as an adaptive mechanism, so it would seem to be intuitively obvious, and correct.

It is said that Kant was therefore wrong to argue that things-in-themselves are unknowable, and that he would probably have changed his mind if he had lived to read Darwin's theory.

This is entirely unrelated to the previous point. They are products of different metaphysical systems, and different logic applies to each. Kant's logic is binary and only applies to dichotomous (Parmenidean) worlds, where things either are or are not. Darwin's theory applies to countably many possibilities, both with regard to an (note, not "the") environment and to its bilaterally interactive elements (such as species). Species affect their environment, and vice versa. The logic is probabilistic on a skewed, random distribution of possibilities.

However, the fact that there is such a thing as evolution at all is something we learn through sense experience (reading and listening), just like any other fact such as that there are mountains, or that ice is cold, or that Julius Caesar ruled Rome.

Not so. Facts are Aristotelian science. They represent an extensive and categorized listing of objects, properties, and relations, as they appear to the senses.

Evolutionary theory is deductive and mathematical, like all other modern mathematical science. Its roots are not in direct observation, but in leaps of imagination (wild guesses), that are exhaustively tested for fit to what does appear to the senses, a posteriori (best fit to mathematical prediction by observation and experiment). This is Pythagorean science, like theoretical physics is.

The truth of evolution is therefore no more certain than any of these other 'obvious' truths, including the existence of the entire world.

Absolutely correct. Evolutionary theory is a best guess, and nothing more. It can be improved upon by later epicyclic methods.

[Neri]

One must be careful not to conflate conceiving of an object with perceiving it. I can conceive of a horse without seeing one [provided, of course that I have seen horses before]. To conceive of a horse, I remember the experience, “horse,” without actually having that experience. In other words, seeing a horse before me and remembering what a horse looks like are experiences of quite a different sort. Based upon my memory of horses, I may also conceive of a unicorn even though neither I nor anyone else has ever perceived such an animal.

Conceiving of a thing is based ultimately upon memory. The memories may be modified or distorted (as is the case in imagining or dreaming). However, one is aware that he cannot bring an object before him by simply conceiving of it. I would suggest that anyone whose experience is otherwise may require the services of a psychiatrist.

But, how is it that we can know that perceptions are caused by real things outside of us and are not themselves pure conceptions? In other words, how is it that we can make the dichotomy described in the preceding paragraph?

We know that perceiving a thing has real consequences that do not obtain when it is merely conceived of.

For example, if I am dreaming that I am being attacked by a wolf, I will awake to find that I am completely uninjured and that there is no wolf in sight. If I am awake and decide to imagine such an event, I know that I will suffer neither injury nor death simply by conceiving it. On the other hand, if I perceive the event, the pain and injury inflicted by the wolf will be proof enough that the perception had a definite connection with reality.

When we perceive the thing we call a wolf, we are sensing the features of it that prompt the brain to reduce the sensation to a recognizable form and retain it as a memory. There is something there that we call a wolf. It may be mostly empty space, but whatever it is, it can do us serious harm. From the point of view of survival, it makes little difference what the “essence” of the thing may be. In fact, it is doubtful that such a thing as “essence” actually exists outside of us. The important thing is that we recognize this dangerous thing should we encounter it again—whatever it may be in itself.

Of course, there will always be some who provide the well-worn argument that the attack of a wolf, whether conceived or perceived, is entirely a product of the “mind.” Such an argument would require the denial not only of the existence of all things outside of us but also of the sense organs and the body itself. Thus, subjective idealism teaches that we are to disbelieve the evidence of our own eyes, because we have no eyes and therefore no sight.

Surely, one who proposes a position so inconsonant with human experience has the burden of proof. However, its proponents tell us that there is no proof to the contrary--as if the absence of such proof can logically establish their proposition. If this approach seems inadequate, they resort to begging the question by claiming that the proof asked for (because it is empirical) is itself entirely in the mind. They go so far as to say that a demand for empirical proof itself begs the question. Thus, they conspire to insulate their ideas from critical examination by setting up precepts that forbid it.

If a person’s beliefs are known by his actions, then no one actually disbelieves the evidence of his own eyes, not even the most extreme idealist. The evidence of the outside world is given to us “on a silver platter,” and we all know it. That evidence tells us, in no uncertain terms, that things happen, not as we would wish them to happen nor even as we would imagine that they will happen—but as they actually happen. Reality does not give a tinker’s damn about our ideas, desires or imaginings. It goes its own way independent of our conceptions.

[DragonFly]

Great post, Neri, all of it.

As a side note, I was thinking about this part, along with my experiments in Photoshop transparency limits to what could still show as an image, even very faint.

Conceiving of a thing is based ultimately upon memory. The memories may be modified or distorted (as is the case in imagining or dreaming). However, one is aware that he cannot bring an object before him by simply conceiving of it. I would suggest that anyone whose experience is otherwise may require the services of a psychiatrist.

So, perhaps the images that we can imagine, such as a purple cow, have to be about 90% transparent, lest we confuse them with real images from external world—and then have to go to a shrink. Now, if one had schizophrenia, the kind with visions, then perhaps this is either like dreaming while awake or the awake imagination producing full opacity of the imaginings.

[Positor]

Neri,

I fully agree with your post. I think the case for realism is very strong. The point I was making in my OP, however, is that invoking evolution does not make it any stronger. If someone insists that wolves are "all in the mind", then to be consistent they should believe that the theory of evolution is all in the mind too.

Besides, this is not just a simple matter of realism versus idealism. There are also the subtleties of the Kantian transcendental perspective (about which there seems to be much disagreement).

[moranity]

it is perfectly possible to construct a model of the world that is detrimental to fitness.
natural selection has given us the ability to construct models of patterns, but the content of those models may, or may not, lead to increased fitness and may, or may not, correspond to patterns that exist in reality.
For models to increase fitness, they do not need to be totally accurate, they just need to make predictions that increase fitness, however you explain the coming of the seasons, predicting accurately the beginning of the growing season will increase fitness.
So, from this view, natural selection is a model of a pattern that may exist in reality, but, regardless of that, it makes accurate predictions, and so, may increase fitness.
So, the idea that the theory of natural selection confirms that our sense inputs correspond to reality, should, rather, be rephrased to the more timid "our sense inputs allow us to construct models that make accurate predictions about future sense inputs, but, also, complete, huge, gaping mistakes that end in cessation of all sense inputs".

[Fuqin]

5. Therefore, things-in-themselves may be completely different from things in the world of appearance.

I think I agree also, however I see another possibility perhaps things in themselves have no appearance outside of an observer, I'm not saying they need an observer to exist what mean is perhaps there is no virtuality to a thing just a behavior, and it’s not a thing that is observed it’s a behavior and by behavior I mean a moving surface without essence,
i.e.( is it a wave or a particle, it behaves like both. What is it then, UMMM ) besides we can’t all occupy the same moment in space and time so perception comes from the center of our individual universes and our disagreement of a thing still tell us something about the thing , that is to say it is continuously indefinable , to surmise the other possibility is that all observations are correct, the interpretation or explanation may not be but some part perception is all the essence a thing may have.
Hmmm I think I may be ranting to much coffee :)

[yadayada]

perhaps things in themselves have no appearance outside of an observer

Lincoln, over at the physics forum, in one of his more brilliant posts suggested that perhaps the universe is made up of all potential energy. In various forms, I suppose. This could also be interpreted as nothing but potential energy in various appearances to us, which would be a rewording of Kant's vision. Everything is potential until actualized by observation made in the special mode of the observer.