What is Logic?

Many times we hear people saying this or that is logical or not logical. But what is logic?

Logic is a system of reasoning that can be scientifically proven. It is a process. The inputs are the assumptions. If we imput faulty assumptions then we can get very stupid but still 100% logical arguments. The basic one is this. Say all men are bastards, and Prince Charles is a man. It is now logical that Prince Charles is a bastard. This argument is 100% logical.

Many of the flaws are found in the assumptions. The assumption that all men are bastards is clearly flawed. Maybe most men. Maybe many men..... and so assumptions must be severely tested and verified before we apply logic to it.

Do you know speeches, scientific treatises can be broken down into "logic symbols" and shown to be logically proven or not?

We need to check our assumptions very very carefully or we can logically arrive at an absurdity.