This is a continuation of this post on Kant.
One way not to argue in support of the Kantian transcendental aesthetic is the way Dinesh D'Souza does in What's So Great About Christianity. D'Souza draws an analogy with a tape recorder, which I discuss in this post and will not repeat here. The problem with the analogy, and similar analogies, is that it is undermined by the very transcendental aesthetic it is meant to support. If Kant is right, and we have access to appearances only and not the reality behind appearances, then we have no way of knowing what is really going on with whatever reality is behind the appearance we call "tape recorder." Whatever thing or things out there in reality give rise to the appearance of a tape recorder, we can't know what they are or are not capable of. They may be capable of all sorts of things we can't imagine; including access to reality in ways we cannot imagine.
The examples generally used to support this sort of argument typically involve animals with different sensory capabilities than our own, like Thomas Nagel's bat (Nagel did not use his bat argument for the point I am making here.) The bat has poorer vision than us, but instead has a highly refined sonar system it uses to echolocate its prey. What must it be like, Nagel asks, to be a bat? What is a "bat's world" like? We can hardly imagine it, but by what right do we claim that our world is the "real world" in contrast to the bat's? If these sorts of examples impress us as support for Kant's views, we should remember that Kant himself did not argue from them. For if Kant is right, then what we call a "bat" is only a construction our consciousness puts on sense impressions. Imagining what it is like to be a bat is just another way of exploring our own consciousness, not a magic way to explore the possibilities of some other consciousness.
There is an illusion involved in arguments like these, as though we can assume for the sake of argument that we do have access to the true nature of things, then argue from there that we don't have access to the true nature of things. If the conclusion is true, then it was true at the beginning of the argument as well as the end. The argument apparently starts with some premises concerning the variety of the nature of things, e.g. the variety between our sensory apparatus and a bat's. What it really started with was the variety in our conscious constructions on sense impressions which, according to Kant, say nothing about any actual variety in reality. So what if the conscious construction we put on sense impressions and call a "bat" has a different character than the conscious construction we put on sense impressions of ourselves and call "men"? Whatever conclusions we might draw from this fact says nothing about the actual sensory capabilities of either men or bats, or the relationship between the two. It is at best about the quirky nature of our own consciousness.
Kant's argument for the transcendental aesthetic is simple and is the only possible one. It starts and ends with the fact that space and time are not conclusions from empirical experience, but the form of it. Kant isn't wrong but, as I argued in the earlier post, we need not accept his conclusions.
But let us grant, for the sake of argument, the natural facts in support of Kant's position to which some of his more naive supporters resort but his philosophy actually doesn't allow. That is, let us suppose that we know bats really do have an excellent echo location system and poor eyesight relative to our own. The argument still does not work. For the bat's echo location system is obviously not intended to discover the true nature of things but merely to help the bat locate its prey; and it serves that purpose magnificently. We see the same thing with the features of other animals. Hawks have excellent vision, but the vision isn't for understanding the world per se, but for tracking prey far below on the ground. The dog's nose is far superior to our own, and the dog lives in a "smelly world", which is perfect for a dog since it hunts through scent.
Our senses, however, and our natures themselves, have no immediate and single purpose the way a bat's sonar is immediately directed toward prey location. We don't hunt by instinct in the manner of a hawk or dog, but must consider the nature of possible prey and how best to capture it. We must understand the world in order to survive in it. Neither are we born with fur like a bear or build nests by instinct like a bird. We must figure out what will work for clothing and how to get it, and what will work for shelter and how to make it. This is why Aristotle says that the relevant distinction with respect to man is that he is rational, which means more than merely the degenerate "thinker" of modern thought, but an animal whose nature is to understand the world. And since we see that nature doesn't fail in its purposes (the bat's sonar does locate it's prey, the hawks eyes do see the mouse on the ground, etc.), why should we entertain the idea that our nature, uniquely among the creatures, fails to do what it is clearly meant to do - and that is to understand the world as it really is?