In this essay intend to consider Hume's criticism of induction. I will further consider how Immanuel Kant seeks to avoids what he perceives as Hume's solipsism through his application of the conceptual scheme. I will endeavor to do this by firstly considering how Hume understands we acquire knowledge about the world and then secondly considering Kant's objection and proposed solution.
Hume asserts that statements can be divided between two distinct groups. The first group he called the 'relations of ideas' which are statements about ideas arrived at by means of deduction. These analytic statements are discoverable by reason alone, and into this group fall mathematics and statements such as "2 + 2 = 4". Their scope is limited to only the relationship between ideas and, according to Hume, cannot tell us anything about the world.
Hume asserts that the latter group of statements are 'matters of fact'. Hume here is referring to statements about the world which are attained by means of induction. Hume later criticises induction; his objective here appears to have been to evidence that certainty is not present within scientific enquiry. Hume suggests that it is always logically possible that any given statement about the world is false.
Hume asserts that induction is a means of drawing a general principle from a series of specific examples to arrive at knowledge about the world. As aforementioned Hume has already asserted that knowledge about the world cannot be arrived at by deductive reasoning. His rationale being that statements about ideas necessitate a priori knowledge (knowledge before experience) and that the world can only be known a posteriori (knowledge through experience). Hume concludes then that if any given statement about the world could be false, inductive reasoning cannot yield certainty.
To understand Hume's claim here let me consider for a moment my wallet. If I were to draw a coin from my wallet it might be a 50p coin. I draw another coin from my wallet and discovered it was again a 50p coin. I repeat the exercise several times, each time withdrawing a 50p coin. I might claim that the last coin I withdrew was a 50p coin, and therefore the next coin will be a 50p coin. However the only way I could assert such a claim would be to conclude that the future will resemble the past. The type of coin I will withdraw is contingent upon what coins are actually in my wallet. Hume's criticism of inductive reasoning is that to yield certainty we must assume that our future experience will remember past experiences. Given this is a statement about the world Hume asserts this statement could be false.
Kant disagreed with Hume that the world is only known a posteriori. Hume had asserted that the mind is effectively tablua rasa at birth, with no knowledge about the world prior to experience. Kant disagreed with the idea that the mind is passive recipient of sense data. Kant suggested that the passive reception of sense data was not sufficient to explain Human knowledge. Kant argued that something has to be done with the sense data received in order to arrive at knowledge. Kant proposes therefore that the mind is not simply a passive recipient of sense data; the mind is active and does something with the sense data rather than nothing.
Kant believed that the sense data is organised according to specific categories which are a part of what we are these are known as Kant's conceptual schemes. Consider for a moment that this essay is stored on the computer as an electronic file. The file is broken down into hundreds and thousands of what are called bits. A bit is a data type that can have two possible values either a 1 or 0. This sequence of binary data -much like Kant believed sense data would be for humans- is essentially useless to the machine unless there is a means by which it can be interpreted. Kant proceeds to argue that we do not receive uninterpreted sense data but that the data we receive has already been understood by means of twelve categories of understanding he suggests are part of what we are.
Kant asserts that as the sense data has already been interpreted, our knowledge and perceptions are not of the 'thing itself' but 'the thing as it appears to us'. Kant distinguishes these objects as the noumena (the 'thing itself') and the phenomena (the 'thing as it appears to us'). Kant asserts that it is not possible for us to access the noumena but that the phenomena is derivative of noumana by means of our conceptual scheme (means of processing sensory data). Whilst Humans may be have twelve categories of understanding, other species may hold different conceptual schemes and therefore percieve the world very differently.
To illustrate the difference between noumena and it's derivative phenomena; consider for a moment a kettle in a well illuminated room. My visual sense perception of the kettle is limited to the visible light spectrum; I perceive it as a particular shape and colour; seeing that it is white and likely made from cheap plastic half filled with still water. I am unable to perceive heat, so without touching the kettle I can't detect if it is warm, hot or cold. Whilst this is a poor example (given my perception of the kettle being warm, hot or cold is already an interpretation of sense data) the point here is that the kettle with all it's attributes (including hot and cold) is the noumena. I can perceive the kettle through my conceptual schema but some properties I am simply unable to access. The Kettle as I perceive it is the phenomena.
