The fundamental problem with rationalism and just using pure reason and logic in general is that logic has no (necessary) connection to reality. It's a game pl

The fundamental problem with rationalism and just using pure reason and logic in general is that logic has no (necessary) connection to reality. It's a game played with symbols, and how you choose to map concepts and things in reality to those symbols determines your conclusion. There's a lot of room to setup your predicates in a way that justifies any conclusion you care to reach, no matter how monstrous, and there are lots of ways to turn remote probabilities into near-certainties. Frequently where they go wrong is injecting infinities or near-infinities into their calculations and once you put the lives of billions of people up against one person almost anything is justified.