Read another response by Matthew Silverstein
It would be unbearable to live a life believing that things like beauty, love, knowledge and life don't matter, and any philosophy that claimed it would be completely alien to me. At the same time, looking at altruism in animals and evolution of social behaviour makes it pretty obvious that our instincts and culture for good evolved for practical survival reasons. Surely it is a bit of a stretch to suppose that by fluke we evolved the beliefs and values that precisely match what is really good and really matters? I'm sure this is a pretty standard question that lots of philosophers have asked, so what kind of answers are there, and how can we decide what is really good or ethical?