What probably happened is that philosophers became popular only if their ideas were simple enough and appealing enough.
On the contrary, philosophers became popular only if their ideas were complicated enough to fill a book. The ideas that were simple enough to be true were also too short to publish.
Eg., I’m not interested in hearing that medieval philosophers ignored the idea that the motion of the planets are governed by the same laws that govern the motion of bodies on earth.
On the contrary, philosophers became popular only if their ideas were complicated enough to fill a book. The ideas that were simple enough to be true were also too short to publish.
An interesting possibility. (Nitpick: “Simple enough to be true” implies that complex ideas can’t be true. This is wrong.)
Can you give an example of a simple but non-obvious truth that was available but passed over in philosophy?
What do you mean by “available”?
Eg., I’m not interested in hearing that medieval philosophers ignored the idea that the motion of the planets are governed by the same laws that govern the motion of bodies on earth.
So, are we looking for something which is:
Simple,
True,
Not obvious,
Was claimed as true by someone or other,
But mostly ignored?
Perhaps Aristarchus and his heliocentrism would fit the bill (while not strictly true, it was truer than the alternative).