**tl;dr** There is no ultimate goal. That may seem to imply nihilism, but it doesn't. This is fine, but in novel situations, I don't know what to do, because I don't know which goal to choose, because there is no ultimate goal.
But now, neuroscientists are directly measuring the neurons whose firing rates encode value and produce our choices. We know a lot more about the neuroscience of human motivation than you might think. Now we can peer directly into the black box of human motivation, and begin (dimly) to read our own source code