Clear and Distinct Ideas


The term ‘clear and distinct idea’ was used by Descartes in his ‘Meditations on First Philosophy’, the book in which he comes up with the famous phrase ‘I think, therefore I am’.


In the ‘Meditations’ Descartes is in search of certainty and, in order to find things that he is certain of, he has decided, quite sensibly, to get rid of all of the things that he is uncertain of and the things that he’s left with when he’s done all of that are going to be the certain ones.


Now, this sounds like a pretty good approach but the problem for Descartes is that he finds out that, actually, when you think about it, you can doubt pretty much everything. For example, your senses are subject to illusions, so you can’t trust them; when you dream, your dreams seem as real as reality, so you can’t be certain that you are awake now and, finally, he believed that you could actually be being deceived by a wicked God who wanted to make everything you believed false, so in fact you can’t trust anything at all.


So what does that leave us with? Well Descartes’ simple but brilliant realisation was that the only thing he was left with was himself. Think about it … if you suffer from visual illusions, then you are deceived but you must at least be something in order to be deceived, if you mistakenly confuse a dream with reality then you, again, must at least exist in order to be mistaken and, finally, if you are being tricked by a wicked God then you must at least exist in order to be tricked. Now, Descartes admitted that he didn’t know what he was but he knew that he must at least be something … a thing that could be deceived, mistaken and tricked, essentially a thing that could think. Hence ‘I think therefore I am’ Here is the extract from the First Meditation where Descartes proves this point.


‘But I had the persuasion that there was absolutely nothing in the world, that there was no sky and no earth, neither minds nor bodies; was I not, therefore, at the same time, persuaded that I did not exist? Far from it; I assuredly existed, since I was persuaded. But there is I know not what being, [the wicked God] who is possessed at once of the highest power and the deepest cunning, who is constantly employing all his ingenuity in deceiving me. Doubtless, then, I exist, since I am deceived; and, let him deceive me as he may, he can never bring it about that I am nothing, so long as I shall be conscious that I am something. So that it must, in fine, be maintained, all things being maturely and carefully considered, that this proposition I am, I exist, is necessarily true each time it is expressed by me, or conceived in my mind.’


Later in the Meditations Descartes goes on to say that this kind of idea is a ‘clear and distinct idea’ which basically means something that is so self-evidently true that it cannot logically be doubted. Descartes then tries to build up a body of certain knowledge using clear and distinct ideas as a test: if it’s clear and distinct then it must be true. This is extract from the Third Meditation where Descartes proves this:


‘In this first knowledge [I think, therefore I am] doubtless, there is nothing that gives me assurance of its truth except the clear and distinct perception of what I affirm, which would not indeed be sufficient to give me the assurance that what I say is true, if it could ever happen that anything I thus clearly and distinctly perceived should prove false; and accordingly it seems to me that I may now take as a general rule, that all that is very clearly and distinctly apprehended (conceived) is true.’


Now, whether or not Descartes was successful or justified in this claim has been argued about for centuries but at this point, however, a more interesting question arises. What exactly makes an idea clear and distinct?


Our first impression might be that an idea is clear and distinct if it makes good logical sense or there is a good logical argument behind it, a logical argument that can’t be doubted. So we might break down the ‘I think, therefore I am’ argument in the following way:


This would seem fairly clear, distinct and indubitable. However, this reading probably isn’t what Descartes meant because it isn’t what he actually wrote down and, if we read the above extract from the Meditations carefully, he just says ‘this proposition I am, I exist, is necessarily true each time it is expressed by me, or conceived in my mind.’ and we should notice that this doesn’t sound like a logical argument at all.


So what makes something clear and distinct? Well, the usual answer is that a clear and distinct idea has a certain logical or rational force that is impossible to deny. However, controversially, it could be argued that, actually, emotion is playing a big role here. An emotional sense of conviction is what makes us certain that something is clear and distinct. We just find it emotionally impossible to doubt that we exist, there is a sense of certainty, a compulsion to believe, a feeling we can’t ignore that ‘I am’ just has to be true. Descartes believed that this compulsion, this sense, this feeling came from our rational minds but it could just as plausibly come from our emotions and so this could be an excellent example of emotion providing us with knowledge. The best bit about it, however, is that, if true, in this case emotion would be providing the basic truth that acts as the basis for an otherwise strictly logical, rational and reason based approach to knowing about the world. A great example of emotion and reason working together to create knowledge and certainty.