People misunderstand that they know everything. Real true selves are unvisibe. Everything is empty. How can we say we know something eventhough we have never seen our true faces. We must study to find ourselves.
People think future or regret past.
After finishing, all in vain. Stupid people try not to sleep to spare time and they dream in day and night. So we are always in dream not real. 100 years is short just same as 1 second. If we are awake moment to moment then we live forever.