In case that we want to define something, that very large areas of boundaries, we can define for what it is not first.
Assume that there is no God, no heaven, no hell; then if for now I kill myself, then nothing left.
So after that time, I have nothing to lose? I live another day with more to get? So between live in despair nor live with embrace every minute with appreciation; which one should be the choice that I should made?
Live without regret? Live with make every minute worth, live to the full. So what the meaning of your living?