Don’t romanticise your “vocation”. You can either write good sentences or you can’t. There is no “writer’s lifestyle”. All that matters is what you leave on the page.

I was going to say work on what you love, but that's not really it. It's so easy to convince yourself that you love what you're doing — who wants to admit that they don't? When I think about it, the happiest and most successful people I know don't just love what they do, they're obsessed with solving an important problem, something that matters to them.

In order to grasp every opportunity, you cannot — you must not — decide your "career path" in advance. Don't have a job fixed in your sights and work backwards — it can be the road to disappointment because you risk passing up opportunities that might take you "off-course."

For example, I was a little surprised when I was talking to a friend who was going to go on the radio. He does work on cosmology and astronomy, and he wondered how he would explain what the applications of this work were. "Well," I said, "there aren't any." He said, "Yes, but then we won't get support for more research of this kind." I think that's kind of dishonest. If you're representing yourself as a scientist, then you should explain to the layman what you're doing—and if they don't want to support you under those circumstances, then that's their decision.

One thing that I went through and I was able to understand is: It's OK to not be OK. Right? Like nobody's perfect.

You know, as Olympians, you set four years to build up to this moment. And then, after it's over, you're kind of lost in a way. You don't really know what to do. You don't know where to go. You don't know who to talk to. And a lot of us do suffer from depression.