See... but I would say that experiential consciousness is unexplained and impossible to measure, and yet, if I were to rank everything based on how certain I am that it exists, experiential consciousness would be at the top of the list. If you take away all of my senses, what am I left with? Just the ability to think and experience my own existence.
Well... you are certain that consciousness exists because you experience it: that is measuring.
As for explaining it, I guess it's more of a definitional problem than a physical one. I'm still confident that one day we'll be able to look at something and approximate how conscious it is.
Free will, on the other hand, requires supernatural phenomenons coming from outside the material world (dualism) to explain how we, humans, can make decisions free of any (or some) of the influences of the physical world. I don't buy it, and I believe the burden of proof falls on the ones who do.
