How do you know you're not dreaming? Or not dead?

Google and ye shall find.

There is a difference between knowing the path and walking the path.

The fear of death never left me; I couldn't get used to the thought; I would still sometimes shake and weep with terror. By contrast, the fact of existence here and now sometimes took on a glorious splendour.

What's so horrible about being dead forever, and not feeling anything, and not even dreaming? What's so great about feeling and dreaming?

He died that day because his body had served its purpose. His soul had done what it came to do, learned what it came to learn, and then was free to leave.