> There's no way to be sure your "consciousness" doesn't die every night and wake up as a new person who thinks they are you every morning.

Yes, omg!!! I was going to say something similar. Possibly the single biggest challenge to advancing the philosophy (or science) of consciousness, is the fact that people have such wildly differing ideas of what consciousness is. The fact is, our wakeful consciousness is dramatically compromised on a regular basis - sleep, general anesthesia, spacing out for a long time, etc. All we have to go on are memories, which obviously aren't the same as consciousness since memories can be stored on a hard drive with the power turned off.

I regularly think to myself, "this may be the first time I've ever been awake. My environment seems to match this brain's expectations, so this brain probably collected data on this environment in the past....but at the time, it could have been anyone's brain"