Descartes would probably agree that the
choice of word to associate with a
particular thing is conventional.
Americans call a certain food "cheese"
while the French call it "le frommage", but
both words signify the same thing.
Similarly, you could write the number four
as "four", "4", or "IV".

But as far as all concepts being
abstracted from sense experience (a
position held by John Locke, who we will
read next) Descartes would disagree. He
would argue that you would never be able
to recognize the commonality of triangles
if you didn't already have some idea what
a triangle was.

Descartes would insist that Geometry,
mathematics, logic, morality and the
concept of God are a priori concepts
which could not have come from the
senses (maybe some of these are better
candidates for a priori knowledge than
others).

Prof. Borrowdale