I stumbled upon the book “When” during a trip to my local library. What a pleasant surprise – I have been pondering about the same question: Why does our mood change somewhat predictably during the day?

It turns out there have been tons and tons research on this. But what Dan Pink is great at is that he does extensive research, and then he internalizes all the information and he can tell a GREAT story. He masterfully did it again with WHEN.

The book is about one fundamental fact of our human beings: Our mood, attention and focus follow a predictable cycle during a day: Peak, trough, and recovery. For most of all, the peak happens in the morning, trough in the afternoon, and recovery in the evening.

The implications are various and profound. For example:

  • Do not go to the hospital in the morning
  • Do analytical work in the morning, mundane stuff in the afternoon, and creative work in the evening
  • Take tests in the morning, if you can
  • Companies should schedule earning calls in the morning
  • Take breaks (e.g. walk outside and short naps) in order to recharge and boost your performance
  • Synchronized singing is good for your health
  • Judges are more lenient right after taking a break. So you should ask your boss for a raise right after her lunch break (or early in the morning), because human beings are more likely to overcome their default choices in the morning or immediately after breaks.

The book answered quite a few questions that I have had for a long time, and gave me guidelines and convictions on how I should things and arrange my life. I hope you will benefit too.