> but it seems to me that for more basic inference operations (lets say add two numbers) power consumption from a processor and a brain is not that different S

> but it seems to me that for more basic inference operations (lets say add two numbers) power consumption from a processor and a brain is not that different Sure it is - it is too hard to figure it out based on 2 numbers number, but lets multiply that by a billion - how much energy does it take a computer to add two billion numbers? Far less than the energy it would take a human brain to add them.