Descartes And The Grink

a) On the essence of material things

Descartes returns to the consideration of matter that he began in the second meditation with the Wax Argument. Here, he introduces the idea of res extensa as being the essential precursor of any particular body. Clearly, what he is relying on here is that such knowledge is a priori (i.e. known without experience) since, at this stage of his argument, he is not yet ready to consider whether his ideas have any counterparts in physical reality. What he is doing is identifying the essence of his ideas – the images that crowd his mind.

The possibility of a priori knowledge was first addressed by Plato. He argued that there existed knowledge that was totally independent of having a body. [This is outlined

Now, not having thought too hard about it, let us consider it more deeply. Does ‘grink’ have implications that I had not foreseen but, on consideration, are implications that I cannot deny – as per Descartes’ criteria? Well, this may be the case. When inventing the term ‘grink’ perhaps we had not reflected on what the necessary conditions are for something being a life-form. We might then discover that regulated reproduction and controlled energy transfer are two things inseparable from being a life-form. Hence, ‘a grink will regulate its reproduction’ and ‘a grink will control energy transfer’ are necessary truths. So, does the term ‘grink’ pick out a true and immutable nature? If it does, then a true and immutable nature could also apply to a winged horse – an idea that Descartes specifically declares as being an invention rather than ‘drawn from his thought’.

Thus, the criteria he advances for justifying a priori knowledge are not well-defined enough to do the work he asks of

In outline, this argument is: God must exist because it is true that I have the idea of a supremely perfect being and it is contradictory to even try to conceive of such a being not existing (since this is less than perfect). What Descartes is saying, in effect, is that existence is a part of the definition of God and so to say God does not exist is to say the being who exists does not exist. Since this is obviously contradictory, we are forced to deny that it could be true (and hence accept that God does