Kant stated a set of categories by which he believed the mind organises raw sense data. These categories include; the categories of quantity, quality, relation and modality. The modern scientific view of the human world is a huge bundle of energy, always changing and moving around. However, we do not see the world in this way, but rather we perceive an ordered world with objects composed of matter that cause events. Part of this order is due to our minds imposing the category of unity upon our perceptions. An example to show how this works is to think about how a computer looks at the world. Computers are useful machines that aid us in doing things that we would find difficult to do on a day to day basis, such as mass calculations or playing chess. However, computers find it extremely difficult to perceive objects in the world, something we would find easy and natural. For example we can easily distinguish all the objects that may be resting on top of a table, whereas a computer reading this information from a digital camera would face a lot of problems. It does not know where the object begins and ends, or even if the object is something separate to the table. Many websites use this technique to prevent computers from automatically registering to websites, in place of real people.
This technique works because the computer is unable to perceive the picture, which has a few distinct letters in front of a background of scratches. It simply perceives a series of marks and blanks and has a lot of trouble picking out each of the letters. This shows that a conceptual scheme is needed for the way we experience our sense impressions. The concept of the letters can only be formed because we already, innately possess the category of unity. This is the idea that there are discrete entities separate from other entities. Without this, our experiences of the world and its surroundings would mostly be unintelligible.
In addition, Kant was confused at Hume’s claim that we cannot have knowledge of the world which can be acquired a priori. Hume argued that all a priori truths were analytic; meaning that they are true by definition alone. For example the claim “All bachelors are unmarried” can be seen to be true just by knowing the definition of a bachelor, which is an ‘unmarried man’. Synthetic propositions, on the other hand, are those where the predicate is not contained within the subject, and so they cannot be known by analysis alone. Therefore, knowledge of synthetic propositions can only be gained through a posteriori. However, Kant wanted to show that synthetic a priori is possible. He wanted to prove that it was possible to establish truths about the world, using just reason that was not simply true by definition. Hume claimed that we cannot know a priori that every event has a cause, however, Kant argued opposite to this view. An analogy to demonstrate this view is the black and white TV. When you have a black and white picture TV, when you turn it on, you might not know what picture you see, however you do know that whatever it may be, it will be in black and white. Therefore this illustrates how Kant could know things about the world that are not true by definition, but could be discovered by reason alone.
However, there are some criticisms to Kant’s theory. It is debated as to whether Kant actually proves his theory. The argumentation is obscure and very difficult to follow, and also not very clear when it comes to establishing the existence of the 12 categories as preconditions of experience. Some philosophers have even challenged the nature of the categories, saying that it is not necessary to have all 12. For example Schopenhauer claimed that we only need causation and substance. Similarly, Strawson stated that it is completely possibly for us to imagine a world without some of the Kantian categories such as space. Therefore, if Kant can’t claim that the category of space is a necessary condition of all conscious experience, then it is difficult to see how Kant can argue anything beyond what might be the case in his own mind. Since he is unable to access all other mind, then he is also unable to correctly express the actual preconditions for all intelligible experience.
Furthermore, another criticism to Kant’s theory is that science now disproves Euclidean Geometry. Kant’s arguments give us an interesting elucidation as to why the laws of maths and geometry apply rather well in our world. He claims that this is because they are derived from the categories that our mind applies to the world. Hence, space would have certain features that the mind imposes on it. Kant then goes on to argue that mathematical propositions are not analytic, so the add to synthetic a priori knowledge. However, on the topic of geometry, science has seemed to disprove Kant’s claims. The concepts that we apply to the phenomenal world (the world that we experience) or “things as they appear”, are broken down in the world of quantum mechanics. It is not very clear as of yet whether the concept of object or even cause, meaningfully applies to sub-atomic particles as they keep going in and out of existence itself. Although this would slightly support Kant’s point that these concepts only apply to the world of appearance, and not to any theories that go beyond this. However, it seems that the world we experience is not Euclidean, even though it does appear that way to us in the scale at which we can see things. Therefore Kant’s claim that we can have synthetic a priori knowledge of Euclidean geometry is not true.
In conclusion I think that although the idea of a conceptual scheme was put forward well by Kant, and supported by examples such as Condillac’s statue and the office and filing system, there were a few problems that Kant faced with the theory. One of the major problems was that his arguments itself were quite obscure and difficult to understand, and the categories which he claimed were all needed to sort out our sense experience into intelligible data, were proven to not all be necessary. In addition to this, theories such as Kant’s theory of Euclidean geometry having synthetic a priori knowledge have now been proved wrong by science. The discovery of sub-atomic particles have shown this, because they are always slipping in and out of existence, questioning whether the concept of object or even cause, meaningfully applies to them. Therefore, it is not necessary to have a predetermined conceptual scheme to make our sense experience intelligible.