day to day life looks at the future

If you could somehow know that our species would never overcome its propensity to divide into clans that subjugate and kill each other, would life still be good? Would you still work for peace?

If you knew that eventually we were bound for extinction, along with all the other flora and fauna on the Earth, could you still live with zest? Would you still have reason to fight for the ecosphere?

Knowing that we will all die, how does that affect how you live day to day?