I understand new language today called "propositional logic" and a whole new world is open to me.

Logic is a great subject, totally underrated.

@RememberMe

The difficult thing is the rule. I understand the individual rule and what is saying but when the rules are join together , everything become too abstract.

I find myself basically translating rule back to English in order to understand what it actually saying. In programming term I am constantly switching variable name and literal in order to understand it.