"Physics has the notion of an observer, which is inherent to all matter." I have no idea what you mean by this. As for circular, I saying it is impossible to

"Physics has the notion of an observer, which is inherent to all matter." I have no idea what you mean by this. As for circular, I saying it is impossible to define consciousness in a way that excludes man made machines (is my computer conscious because it is aware of other similar machines on the network, as well as its own place in the network? Is a self driving car conscious because it is aware of its position in space relative to other cars?), without simply using other words that have similar meaning. People define "conscious" using words like "aware" or "feel" or "think", while being quick to assume that all words don't apply to machines. But they won't explain why not. This goes into detail about circularity of definitions: http://www.karmatics.com/docs/dictionary.html http://www.karmatics.com/docs/dictionary.html