How the Critique of Pure Reason solved 2000 years of metaphysical confusion but still is ignored

The Critique is often considered the most important philosophical book ever written so it isn’t underrated. What is true, however, is that the problems it solved still trouble many who remain ignorant of Kant’s work. In the AskPhilosophy subreddit, questions about determinism appear everyday when after Kant’s treatment of the concept of cause such problems should be settled. A reading of the Critique would also benefit people in more formal academic fields as sciences in general or philosophy of science as the concept of cause is central in such disciplines.  Here, I will provide a quick overview of Kant positions.

It’s essential to understand the Critique to bear in mind the two main philosophical positions that existed before Kant: empirism and rationalism. Rationalism thought that all knowledge could be achieved in a purely deductive manner, that all that was needed to know the world was the human mind and that the senses only provided a more obscure version of the world. Empirists, on the other hand, believed that all of our knowledge had an origin in our senses. This way Hume goes to the extent of saying that the concept of a cause is nothing more than the result of a human habit to associate what frequently appears in succession. The Critique of Pure Reason was meant to overcome these two positions and give reason the limits of what it could legitimately expect to gain and what was beyond its abilities.

Here I won’t dig into the structure of the book or it’s arguments as there are plenty of resources that do that. I’ll simply mention Kant’s positions regarding the status of the components that make up the human mind and the powerful philosophical thesis that arise from them.

Kant makes a cutting distinction between what exists in us and what’s outside. What is in us is the world as we know it: the phenomenological world that is a result of the contact between what’s outside us and the structure of our mind. What’s outside is the noumenical world, that is, the world as it exists independently of a human knowing it. About this world we know absolutely nothing as by definition what we know belongs to the phenomenical world. From this perspective, Kant proceeds to explain what is time, space, a cause, a judgement, etc. Kant will tell us that all of these arise from the structure all rational beings’ mind has.

Among these structures we have the categories of understanding and among them we have “causes”. These are filters that organize the material received by our senses. This way a cause is something that’s imposed by humans to reality. One can feel as the western equivalent of a Zen monk when you realize the power this idea has. A cause doesn’t belong to the structure or reality, when we say that x causes something y we are not talking about reality but our reality.

Now the question may arise if science has a point after all. Why study reality when all that we are discovering is a human fiction. The problem of the correspondence of reality with our vision of the world build upon the succession of causes isn’t clear but one can deduce that was easily settled by the infinite power Kant gives to reason, the universal and necessary character of the rational mind. Nowadays we can’t accept such metaphysical belief and know that the human mind is just another physical phenomenon, dust which became complex as a result of millions of years of evolution. Modern science is, more often than not, conscious that what it deals with is nothing more than models which only aproximate reality in an always partial way and that will be forever subjected to change and further approximation. These ideas are clearly Kantian influenced although Kant thought there were transcendental “models”, if we can use that anachronism, such as Newton’s physics which were build upon the transcendental human filters of time and space that we impose to our phenomenological world.

Having in mind these basic outlines of Kant’s philosophy we can easily get rid of any form of determinism. If a cause exists solely inside the human mind, then claiming that the reality independent of humanity and humanity itself is determined by cause is an illegitimate claim. One which extrapolates a human fiction to something real.  Unfortunately, many scientists don’t bear in mind these discoveries and pretend to make out of their very valuable work a metaphysical cosmology. We see mathematicians thinking that there are studying the rules of the universe when they are working with an abstract logical language which may have application in modelling reality. We see a Stephen Hawking claiming physics can know the whole of reality when humanity will never find something they can’t ask why to.