Ayer's Criticism Of Priori Knowledge

A.J. Ayer attacks the rationalists view that a priori knowledge is better than a posteriori knowledge. He states that a priori truths cannot tell us anything about the empirical world using the mathematical truths, which are a priori, as an example for this. He also states his Verification Principle, which argues that in order for a statement to be deemed meaningful it possess conditions under which it can empirically verified, as a criticism of the rationalist view. However, this principle is fundamentally flawed because it’s reasoning is hypocritical as it can’t empirically verify itself and so doesn’t work.

J.S. Mill went so far as claiming that mathematical truths are in fact no necessary stating that we may in fact be mistaken when it comes to our observations of the workings of maths. For example, five plus three could in fact equal nine but we have just been miscounting all this time. This, hence, means that maths is not a necessary truth. However, many would argue that this is too big of a leap to make and just leads back into empirical scepticism.

Whilst there are many criticisms of rationalism, there also some problems with empiricism too, some of which

He stated that the empiricist view is wrong because the mind does not merely passively receive knowledge through the senses without categorisation yet the rationalist view is also wrong because one can’t just use reason alone as you need to be able to understand the physical world. Instead Kant saw that true knowledge required a combination of both, rather than either one or the other, to organise and categorise a series of empirical experiences in the mind, which forms knowledge. This also led to his criticism of Hume’s Fork which states that there is such a thing as the a priori synthetic, an example of which would be a maths problem such as seven plus five equals twelve which we only know through experience of using maths yet is also necessarily