PHL100: Descartes's Meditations I and II
Descartes's Meditations I and II
Background on Descartes
- Lived 1596-1650
- Accomplished mathematician, devoted to the development of
science, but appears also to have eagerly wanted to reconcile
science with the Christian beliefs of his time
- Schools were dominated by a set of views called
"scholasticism," which was a combination of Aristotle and
- Descartes aims to reject scholasticism with a radical new
start to human knowledge (rejection of Aristotleanism and
scholasticism was a key feature of the leading scientific
thinking, such as in Galileo). The Meditations are his most
compelling attempt to develop this new foundation
- Note: these meditations are Descartes alone! Knowledge
is not for him being led by a teaching but rather by
- Descartes decides to begin by withholding belief in
opinions which are not certain. This can be done through
systematic doubting - by attacking his most fundamental
- He has always assumed that sense were his primary source
of knowledge, BUT
(Note that in dreams and imagination we compound things to
make new things - this suggests that compound beliefs are more
dubious than simple ones.
- Mad people see things that aren't there
- Dreams seem real when we have them
- But cannot one assume God exists? Descartes piously says
that we can, but agrees to set this issue aside.
- A thought experiment: assumer there is an evil demon or
power that generates a complete deception occurring all around
me, and for all of my senses, for the duration of my life.
Now, is anything certain?
- Descartes begins by doubting everything, and asking what
remains (what cannot be doubted)
- "Cogito ergo sum"
- What is the thing that thinks?
- Not a "rational animal" (scholasticism's definition)
- Not a body that walks, eats, etc.
- Not a sensing thing
- BUT: a thinking thing. I exist as long as I am thinking.
- Imagination cannot tell me what I am
- Doubt, understanding, affirmation and denial, will,
refusing, imagination are all features of thought that cannot
be without me
- How do we then understand bodies? Primarily through
reason. Example: I know that infinite variations in form are
possible for wax, but these cannot be perceived or imagined
- Reason grasps the true nature of wax
- Perception is mental inspection
- Truth is known when we understand clearly and distinctly
- Judgment leaps beyond what is given in perception