The Scottish Philosopher David Hume (1711-76) is widely known for his sceptical attitudes to certain types of knowledge. As with the other Empiricists, Hume disagreed with such philosophers as Descartes that the mind contained innate ideas. He also criticised the idea that we could be certain about anything outside of our experience that it is so.

Hume's Fork

Hume divided knowledge into what he termed "relations of ideas" and "matters of fact". Relations of ideas are what we have been calling analytic truths or a priori knowledge. These are such things as "All bachelors are unmarried", "2 + 2 = 4", etc. These are certain in as much as we cannot conceive of them being otherwise. Matters of fact, however, can be falsified. I may say, "The sun will rise tomorrow" (which is extremely likely) - but is not impossible that it will not.

Ideas and Impressions

For Hume, ideas are simply weaker versions of sense impressions. So, for instance, the idea of the Sun is not as vivid as actually looking at it. Furthermore, no can exist in the mind without either first being experienced or formed through the combination of other experiences.

Exercise

How might Hume account for the following ideas?

1. A mermaid
   
   
2. A golden mountain
   
   
3. Heaven

Causation

The Rationalists argued that there was such a thing as necessary connection. We looked at the idea of necessity earlier and saw how it was meant to show that certain things were the case because mathematical or logical principles meant that they could not be otherwise.

However, Hume argued that all our knowledge of cause and effect came through habit. So, for instance, if we see the Sun rising it is not because it corresponds to some eternal and unchangeable law, but because we have seen it rise countless times. Therefore, the more we have experienced things, the more certain they will be.

Question

For Hume, cause and effect is nothing more than habitual perception. Are there any examples that might contradict this? Also, Hume sees miracles as being unlikely for this exact reason - that they have not been observed often enough. Can this view be criticised?