The first half of this book contains "Rules for the Direction of the Mind", "Discourse on the Method", and "Meditations on First Philosophy"; and honestly the first half is all I've read (and reread, and reread, etc.) This is some of the most logically thought out and clearly expressed philosophy you will find anywhere. Not only that, it covers all manner of significant topics such as the existence of things, our own existence, our own perception of our existence, God's existence, the extent to which it is possible to doubt, and so on. Reading this you will find that "I think, therefore I am" misses many of Descartes' most important and skillfully executed arguments. I highly recommend it! ( )