The Limits of Human Knowledge
Is there a limit to the amount of things that we can know?
We have…we are part of the five great apes, like to gorilla, chimpanzee, orangutans and gibbons, and humans are one of them. All of them show a high degree of intelligence, a high degree of community, of emotional attachment, and language – in very, very crude ways in the case of the other four apes – but in the last thousand years, the human brain really developed and grew to enormous proportions with respect to the others and was able to develop other activities so that, I don’t know, the way we use our hands, the way we use our language and the way we perceive the world has been very unique with respect to higher mammals: apes, elephants and cetaceans have also very evolved brains, they can communicate and they can exhibit and show a lot of emotions and family and community sense. But, yes, we see limitations there in those brains and we have perhaps gone a few steps beyond those limitations but it does mean in our own turn, we are also a limitation for something that will be the super human that may develop in the future and there are things that by the limited nature of our mind, of our brain, we cannot access at the moment, although we have to be patient; if we see how these developments take place and how long it takes to develop…I mean, the difference between our brains and the brains of people who built the pyramids is zero, it’s the same brain, just the amount of information that is being accumulated in those few thousand years that makes us superior in a way. Paraphrasing Newton: very famously that he says, if I have achieved anything it’s because I have been standing on the shoulders of giants. Well, there are a lot of giants behind us and then we are the giants that other people will take…I mean given the proportions, the scale, but I don’t know in the future.
I remember Stephen Hawking gave a beautiful summary of his life, biographical life, in the Royal Albert Hall – Jim Al Khalili was chairing that, it was packed with people – launching one of his latest books and at the end there were questions from the audience, pre-recorded and he had recorded his answers. And the last question was, Professor Hawking, do you think that we will know, one day, everything about everything? Again, the other…coming back to philosophy, this is the limits of knowledge that the philosophers…is there a limit to the amount of things that we can know? Will we reach that limit, Professor Hawking? And he said, I hope not.
And I knew he was going to, because that is what makes us human. That not knowing is fundamental. Einstein said, the most beautiful thing is the mysterious, when we don’t know, we have that challenge. That’s what has kept this brain developing along history, the not knowing. And, yes, there are lots and lots of…the more we find, the more we know that we didn’t know. We open windows to the mysterious, more and more windows that we didn’t know were there. So, yes, one of the things I would like to…if you imagine in a few hundred or thousands of years we come back to this planet and see what human kind – if they survive – what is the state of knowledge then? Did they find what dark matter is? Did they find what dark energy is? Was it all wrong? Was it some, I don’t know…did they find where is the Big Bang coming from? Were there other universes? Did they find alien life? All these fundamental questions that we still don’t know, we are still struggling, and as I said we have to be patient, these things take time. It’s not going to be sorted out in two or three or five or ten or a hundred generations, we’re just starting; the adventure of human beings just started a few thousand years ago. Life on Earth has been for billions of years. So if we survive the next, I don’t know, 100,000 years…I mean, in the last few hundred years we have achieved so much, since the invention of the telescope and the microscope, in 400 years, let alone in 1,000 or 10,000, 100,000 years, the amount of things that we will know and the amount of things that we will know we didn’t know!
So it’s fascinating, it’s fascinating. Richard Feynman was asked this question and he was dealing with the idea of not knowing and he said, well, I’m not frustrated, I’m not anxious or sad that I will die not knowing. I know that I know more than Einstein, I know more than Newton, I know more than Maxwell etc., so I am just part of that chain and, in the future, people will come knowing more than I know now.