Without that structure, I ended up feeling overwhelmed.

Oh ya, I doubted more than expected. I had doubts all the time. The way was extremely, extremely difficult. … At one point I had to describe what I am doing to a person who is a great intellectual but not a scientist, and I told him what we felt is that we are climbing mountains in order to reach the climax – and these mountains are like the Everest, the biggest most difficult to climb – only to find out that there is another mountain waiting behind it to be climbed afterwards. So every climbing was an achievement but there was a bigger problem behind it or above it. I had lots of minutes that I didn't expect, but I thought science in general and this science particularly is worth the effort – even if we would never get the ultimate result.

Don’t panic. Midway through writing a novel, I have regularly experienced moments of bowel-curdling terror, as I contemplate the drivel on the screen before me and see beyond it, in quick succession, the derisive reviews, the friends’ embarrassment, the failing career, the dwindling income, the repossessed house, the divorce . . . Working doggedly on through crises like these, however, has always got me there in the end. Leaving the desk for a while can help. Talking the problem through can help me recall what I was trying to achieve before I got stuck. Going for a long walk almost always gets me thinking about my manuscript in a slightly new way.

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.