(a) you’re robust and resilient enough to handle whatever occurs, (b) you can’t do anything about it anyway, and (c) you’re looking at a big-enough picture and long-enough time line that whatever you have to accept is still only a negligible blip on the way to your goal. We’re indifferent and that’s not a weakness. As Francis Bacon once said, nature, in order to be commanded, must be obeyed.