Rationalism
As a rationalist, you believe that knowledge is a priori; it is independent of experience and can be derived from reason and intellect. An example of a priori knowledge would be ‘all squares have 4 sides’ we do not need to check that every square has 4 sides because by definition a square has 4 sides. In this sense all a priori knowledge is analytic since we do not need to experience it to know it is true. Rene Descartes claims that we have a variety of ways to gather information, such as the concept of maths. Mathematics is technically flawless since it follows the order of analytic truths that are necessary truths. 2 + 2 = 4, this is true and saying otherwise would deem this equation contradictory. In this sense mathematics (as said by Galileo) can be applicable to everything in existence since anything can be reduced to its foundation of numbers, be it the size or area of something or the density of atoms within it. Bacon believed that mathematics is the key to science; science is completely made up of synthetic propositions and we can therefore derive that, regarding Bacon’s claims, synthetic a priori knowledge is possible which leads us to believe that mathematics and its existence acts as a key role in the theory of synthetic a priori knowledge.
Rationalists believe knowledge is innate or can be grasped through logic. This would therefore suggest that that we can know things independently, without experiencing them, by means of a logical thought process; however the idea of synthetic and a priori knowledge may seem contradictory since synthetic knowledge is not strictly obtained innately. In terms of synthetic knowledge, you must understand the concept before you can grant the contingency of the idea. Empiricists would argue that all a priori knowledge is based on analytic propositions and therefore synthetic a priori knowledge is impossible. However once a rationalist can understand simple concepts, one can create a new idea which can be interpreted as synthetic a priori knowledge.
Empiricism
As an Empiricist, you are to believe that all knowledge comes from experience; in contrast to a rationalist you do not consider that there is innate a priori knowledge, nothing that gives you any understanding of the world given to you from birth. Empiricists are strictly a posteriori. John Locke claims that at birth we are void of all knowledge. This is known as Tabula Rasa; meaning that we are all born as a ‘blank slate’ which he claims we have no a priori knowledge of anything. With this being said we are therefore led to believe that we can only grasp knowledge of the world through our sense impressions; an external experience using our five senses of touch, taste, sight, smell and sound that are so forceful and vivid it is impressed upon us ‘like a stamp’. These stamps ‘furnish’ our blank minds as we go through life.
David Hume, also an empiricist, claims that our ideas are not our own, they are merely copies of an original sense impression, for example an idea of ‘hard’ or ‘grey’ are just copies of sensing hard or grey from seeing and touching a rock. A rationalist might argue that this is not true, how could you have the idea of a unicorn when it is a mythical creature? You can still have the idea of it without experiencing it. This would agree with the argument that there is synthetic a priori knowledge. Hume would counter with the explanation of we can only have the idea of a unicorn because ‘you’ve experienced a horn and you have experienced a horse’.
Considering this, we can say an empiricist would believe that there is no such thing as synthetic a priori knowledge; instead Hume suggests that you have complex ideas. Complex ideas are combining two or more experiences together to create the idea of something new. Take the colour red and a tree for instance; you could easily come up with the idea of a red tree. This is indeed synthetic knowledge and a rationalist would say this is a priori since we have never experienced a ‘red tree’. However an empiricist would argue that this is simply not the case, although it may be synthetic it is not a priori since you have experienced the colour red and a tree.
Kant’s synthesis
Kant’s synthesis agrees that we can have synthetic a priori knowledge. He states it is evident that Rationalism and Empiricism had both failed to prove that all of our knowledge has come from or conform to objects and he notes that in order to experience anything he must be doing it within time and space. Considering this, space and time therefore become necessary dimensions needed to experience anything; however if this is so we could not experience the concept of space and time because we must first have the dimensions of space and time and this therefore shows that we must have ideas of space and time a priori because otherwise we could not experience anything. Kant suggests that we can have a priori knowledge because not all truths we experience are analytic, and this therefore means that since we know these things a priori through space and time we can have synthetic a priori knowledge. Kant’s synthesis combines the ideas of rationalism and empiricism and creates a theory that the mind has three categories: Sensibility (Empiricist) Reason (Rationalist) and Understanding (Empiricist and Rationalist). Kant claims the rationalists were right to think that a priori knowledge is possible, only instead of a priori revealing the structure and anatomy of things, it reveals the structure their experience must have.
Conclusion
After considering the claims on rationalism I have demonstrated how one can have synthetic a priori knowledge through understanding simple concepts and combining them into a complex idea. I have also assessed the arguments against rationalism from the empiricists who claim that all knowledge is derived from experience and therefore cannot have a priori knowledge at all. Nonetheless I have decided that we can have synthetic a priori knowledge; Kant’s synthesis, in my opinion has supported the idea of rationalist a priori knowledge and the theory on space and time reinforces my argument. However for others to decide whether it is possible to decide whether synthetic a priori knowledge can be, I believe that it is completely down to the individual. If you are loyal to the empiricist view then you would not agree with the thought of synthetic knowledge. But if your heart beats with the likes of Descartes and Galileo then you would agree with the idea.
Chris Septim
Synthetic A Priori Paper Page
