Question 1

What is the best book to start with?

Accepted Answer

Discourse on the Method, parts 1, 2, and 4, then Meditations 1 and 2 in Cottingham The Discourse gives the public project. The first two Meditations show how much slower and smaller the foothold is than the slogan.

Question 2

What is the most famous quote?

Accepted Answer

This library does not measure fame, and it does not rank lines by how often they are shared. The first line it files for René Descartes that is not marked Questionable or Misattributed is “I think, therefore I am.” (Discourse on the Method, part 4 (1637); Latin cogito, ergo sum in Principles of Philosophy I.7 (1644), Paraphrase or translation).

Question 3

What is the most misquoted line?

Accepted Answer

None of the lines this library files for René Descartes is marked Misattributed or Questionable. That is a fact about these cards, not a certificate that every popular sentence is theirs.

Question 4

What is one key idea, in a sentence?

Accepted Answer

Methodical doubt: A seeker should, once in a life and as far as possible, suspend whatever can be doubted in order to find what remains.