Do not block the way of inquiry.

The entire universe is perfused with signs, if it is not composed exclusively of signs.

The idea does not belong to the soul; it is the soul that belongs to the idea.

By an object, I mean anything that we can think, i.e. anything we can talk about.

Without books, God is silent, justice dormant, natural science at a stand, philosophy lame, letters dumb, and all things involved in darkness.

Philosophy is based on speculation, on logic, on thought, on the synthesis of what we know and on the analysis of what we do not know. Philosophy must include …

Neither acquiescence in skepticism nor acquiescence in dogma is what education should produce. What it should produce is a belief that knowledge is attainable …