This answer has 4 letters and comes to us from the daily newspaper, the N.Y. Times, aka., New York Times crossword puzzle.
Here is the correct answer for the "Philosopher Descartes" crossword clue.
After searching the internet using the following sites, www.google.com, and www.ask.com here is what I found.
If this is the correct answer, please click on like button! - RENE
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