Explain Hume's theory of impressions and ideas. What, if anything is wrong with it?
Explain Hume’s theory of impressions and ideas. What, if anything is wrong with it?
David Hume (1711-1776) was a very influential empiricist and an essential member of the enlightenment. He believed that all knowledge originated from experience and did not believe (as other philosophers of the enlightenment (such as Kant) did) that knowledge was attained through pure reason. Hume also rejected the claim that there is such a thing as innate, a priori knowledge. During the time in which he lived Hume had observed the success of the natural sciences in providing some form of regularity within the events of nature; he saw that biology and physics could be applied to the natural world in order to understand the way in which it evolves and changes. Being a naturalist (someone who believes that everything can be clarified in terms of the natural sciences), Hume saw no reason why the same principle could not be applied to the human mind. Humans are part of nature and therefore the mind is part of nature. In that sense Hume argued that just as principles can be applied to the events of nature to enable us to understand it, similar principles can be applied to the human mind, and it can therefore be explained through empirical research (Blackburn, 1996, p179). He set about establishing this in his Treatise of Human Nature (1739) and went on to write An Enquiry Concerning Human Understanding (1748) where he laid down the groundwork for his theory of impressions and ideas which he believed to explain the workings of the human mind. The theory of impressions and ideas is central to empiricism as it attempts to explain the human mind and thought processes through sensory perception and experience.
Hume argues that the mind is made up of impressions and ideas. Impressions are the first initial experience of anything within the material world and ideas are the recollection of impressions. For example, if I trap my finger in a door then the immediate sensation of the finger being trapped is an impression. If later, I tried to explain to a friend how painful it was when I trapped my finger in the door I can recall the incident in the form of an idea. However the difference between the impression and the ‘copied’ idea is that when I recall the experience I can remember but not feel a physical pain; the point being that the idea is much less vivid than the impression and has much less impact (Hume, 1999, p96). Hume himself stresses that even “the most lively thought is still inferior to the dullest sensation” (Hume, 1999, p96). He argues that ideas are the machinery of the mind, they allow for a sense of self, imagination and learning. Hume accepted that counter arguments to this claim may arise such as the difficulty in explaining how those things which we imagine, that we have no first impression of can come to be. Hume explained such imaginings through the theory that impressions and ideas can be both simple and complex. He said that no ideas were ever innate therefore ideas, for example talking animals (which we have never experienced as a single impression) are what he called complex ideas. This is where the imagination merges two or more ideas to develop a complex idea. For example, the idea of a talking lion is developed by taking the idea of a lion and fusing it with the idea of human speech. Therefore no ideas are ever innate. Hume attempts to prove this by asking the reader to examine the contents of their own mind and produce any idea which does not have some form of related impression. Hume also clears up a few problems before they arise. For example, ideas are always copies of impressions as opposed to impressions being examples of ideas. This is because impressions are always experienced first and then an idea of the impression follows. Hume uses an example of a blind man being unable to form a simple idea of a colour due to the fact that he has never experienced colour as a simple impression (Hume 1999, p98). Hume then attempts to clear up another possible counter argument which he calls the ‘missing shade of blue’. He imagines a scale of all the possible shades of blue from the darkest to the lightest and asks himself whether, if one of the shades of blue were missing, a person who had never seen that particular shade of blue might still be able to produce an idea of it without ever having a previous impression. Hume admits that this may be possible but does not offer a sufficient response to this possibility as “this instance is so singular, that it is scarcely worth observing” (Hume 1999 p99). Although Hume’s own answer to his own possible argument is not completely adequate, in his defence we could argue that the idea of the missing shade of blue could be a complex idea, constructed by merging the other ideas of blue together.
