The most horrifying journey, this is what doubting 'everything' does.

[Edwardo Piet]

There is no reason not to reason, but it's about distinguishing proper ways and non-proper ways. 

Aristotle worked most of the fundamentals out thousands of years ago, and way before the Quran was written.

Aristotle was wrong about a lot of things, but the fundamentals of logic he spelled out are absolutely foundational.