When clocks get out of step, there is no universal 'now' or present moment on which the different observers can agree(at65)
"What I want to know is where Betty is now." In Ann's frame of reference, Betty is 7 x 0.8 = 5.6 light-years away. That is all that can be said(at66)
Carnap conceded that there is "something essential about the now." But expressed the belief that, whatever it w, it lay "just outside realm of science."(at77)
The human now is not simultaneous with the visual stimulus, but a bit delayed, allowing time for the brain to reconstruct a plausible fiction of what has happened a few milliseconds before. The intervening motion is produced retrospectively, built only after the second flash occurs and projected backwards in time(at267)
The "sorting out" of temporal sequences better not take too long, or we could be hit by a falling branch while we mull the situation over. It follows that the human "present moment," revealed now in all its psychological and physiological complexity, cannot last for more than a fraction of a second. Consciousness is the result of an evolutionary process of any sufficiently organized medium(at272)