[A]s I got more experienced in New Guinea, I realized, every night I sleep out in New Guinea forest. At some time during the night, I hear the sound of a tree crashing down. And, you see tree falls in New Guinea forest, and I started to do the numbers. Suppose the chances of a dead tree crashing down on you the particular night that you sleep under it is only one in 1,000. But suppose you’re a New Guinean, who’s going to sleep every night in the forest, or spend 100 nights a year sleeping out in the forest. In the course of 10 years, you will have spent a thousand nights in the forest, and if you camp under dead trees, and each dead tree has a one in 1,000 chance of falling on you and killing you, you’re not going to die the first night, but in the course of 10 years, the odds are that you are going to die from sleeping under dead trees. If you’re going to do something repeatedly that each time has a very low chance of bringing disaster. But if you’re going to do it repeatedly, it will eventually catch up with you.
That incident affected me more than anything else, because I realized that in life, we encounter risks that each time the risk is very slight. But if you’re going to do it repeatedly, it will catch up with you.
He has a new book out, The World Until Yesterday: What Can We Learn from Traditional Societies? which, given his prior work, I will probably read at some point.