Dr Goodall only said this once, and I don’t think it was intended to be a key lesson in that particular lecture. The value of this statement is how much human behaviour it illuminates. We’re not really rational, thinking beings, unless we have to be. We’re adaptation executors. We form a view of the world, and defend it from challenge.
People of different politics, religions, or cultures are obviously a challenge to our views. Those closer to us can also be a challenge as well, perhaps emphasised by their proximity. People will condemn those with different priorities, those who react differently to important situations, or even those who enjoy different pastimes.
In the past I have condemned or dismissed people for doing many things I now enjoy, including things as trivial as lifting weights or playing video games, or as consuming as studying economics or biology. I’ve been condemned myself for being vegetarian (without ever attempting to convert someone), for studying business, and for having different spending habits than the next person.
The previous paragraph was not written to evoke pity, or to act as a mea culpa. I consider myself unusually open-minded, and I would try not to make the same mistakes again. Instead, think about how much of the condemnation of others you hear is not merely made possible by difference, but driven solely by difference, however trivial. The Robbers Cave Experiment is a prime example of this.
I could spend a while working out why we do this, but I’ll spare you. Instead I’ll just say this: for all the limitations of pithy phrases, and for all the dangers of thinking or reasoning with only basic models, there is still a real value to having a catchy summary of a complex set of issues.
On some level, I knew the truth of Dr Goodall’s words before he spoke them, but I’d never condensed them so neatly in my own mind.