So time is  related to causation ?  Like as the  flow of information in a system each time the system change states ? And so did our brains evolve to perceive this changes and back dependencies as the "flow" of time itself ? I don't get it.... and how's that fundamental?     Feels like he's saying that we cannot go back in time... because all the "states" necessary for us to exist in the past would not exist.   I'm so lost.....   Lex I want my brain cells back.... Don't judge me... I'm not on drugs I'm on Lex.