Descartes

1. Descartes' entire philosophical theory is based upon systematic doubt. This approach at the world is certainly different from the majority of Descartes' predecessors. You asked for context, so here it is. Prior to thinkers such as Descartes, most philosophers (and especially theologians) emphasized a belief in something, rather than knowledge about that thing. Descartes' thinking comes after what is now known as the Epistemic Turn. The Epistemic Turn refers to the point in time when philosophers (and others) began to stress the knowledge of something rather than the belief in something. From this mode of thinking, Descartes sought to establish a starting point; he sought to find that one thing that could never be doubted. Therefore, doubt everything until you find the one thing that you know is absolutely and necessarily true. Descartes sought to begin again from the foundations.

Well that sets the stage for this excerpt. Descartes proposes a wild concept. Up until this point, Catholic theology always portrayed God as all-good. Descartes comes along and says he is the "evil genius," the "deceiver." According to Descartes, even such concrete principles as 3+2=5 may not be true, since God may be deceiving us into thinking so. Descartes is not saying that this is the actual case, but because he can doubt it, it may be possible.

2. Descartes here is saying that he is certain of only one thing and that is that he is a thinking thing, not a bodily thing. The only thing Descartes thus far cannot doubt is that he thinks. Everything else, including his body may not really exist. According to Descartes, he has direct access to the fact that he thinks and that no one could ever tell him that doesn't have the thought. Descartes here says that "everything I very clearly and distinctly perceive is true." But we find from reading on that, no this is not always true. We do not assert that nothing outside of us exists, but we can doubt that nothing outside of us exists.

Once again, we return to the problem of the evil genius. 2+3 may appear to be 5, which is something I can very clearly and distinctly perceive as being true, but God may be deceiving me. Ultimately we learn from reading on that Descartes says he has no certainty.

3. In order to understand this excerpt, one must understand Descartes