“Nothing in the universe is known to be cooler than about one kelvin – except in certain physics laboratories on Earth.”
If I had to choose but one sentence in the library of humanity to fill me with hope, it would be this one. It’s a paean to the creative power of humanity, to the power that knowledge plays in our lives. It’s an example of the Sages’ ancient wisdom - “become a partner with God in His creation.” It’s a rebuttal to Stephen Hawkings’ most pessimistic view of man, that we are but scum of the Earth.
Knowledge is the human superpower. Oxford theoretical physicist David Deutsch explains that we can take the natural world, the laws of physics, and harness them for our own purposes. We can use the knowledge contained therein to create new things, things never before seen in the history of time.
Like a fridge that sits at half-a-billionth of a degree above absolute zero, the coldest temperature allowed for by the physical laws of the universe.
This makes Deutsch, by his own words, an optimist. An optimist, not in the sense of thinking that everything will work out in the end, but in the sense that, since problems are soluble, we can and will solve them. This is the true power of knowledge - it’s a key to unlock infinite doors, to progress forward on the infinitely long journey of understanding ourselves and our universe.
More than a mere pioneering quantum physicist, Deutsch is also a philosopher of science, trained in the Popperian tradition. It is through this lens that he's written his two major popular books Fabric of Reality and The Beginning of Infinity.
Deutsch has many breakthrough ideas, but arguably his most far-reaching are about knowledge and the possibility that the universe holds. In his account, knowledge is always conjectural, open to disproof and revision, as opposed to certain and justified. He calls this way of thinking “fallibilism” and sees in it the secret to scientific progress:
Fallibilists expect even their best and most fundamental explanations to contain misconceptions in addition to truth, and so they are predisposed to try to change them for the better. … Moreover, the logic of fallibilism is that one not only seeks to correct the misconceptions of the past, but hopes in the future to find and change mistaken ideas that no one today questions or finds problematic. So it is fallibilism, not mere rejection of authority, that is essential for the initiation of unlimited knowledge growth – the beginning of infinity. 
Deutsch’s optimism is fueled, in part, by his recent work on constructor theory, a theory of physical laws that he devised with his colleague Chiara Marletto. Deutsch and Marletto aim to expand the expressive power of physical laws by focusing not only on what is but on what could be. This would allow for theories of computation and information, as well as knowledge, to be brought under the rubric of physics and to be studied and quantified more rigorously than in the past.
Unlike many of his colleagues, Deutsch is a champion of humanity. “People are significant in the cosmic scheme of things”. This view imbues each and every human life with incredible sanctity. Each one of us is capable of contributing to the world, of furthering knowledge, of fulfilling the Biblical mandate “And God said to them: be fruitful and multiply. Fill the land and master it.”
Through Deutsch’s worldview, I finally understood what it means to live life as prayer.
Jordan Peterson, when asked if he believed in God, would often respond that he acts like he believes in God. Deutsch is a self-professed atheist, but to this I always say, “he thinks he doesn’t believe in God, but just read his books. There’s no one alive today who believes in God more than him”.
To get more of a flavour of Deutsch’s writings and philosophy, check out these links:
Sam Harris and David Deutsch’s podcast are excellent opportunities to see Deutsch’s ideas in action, as well to have some of their implications worked through and challenged.
- Sam Harris and David Deutsch’s first conversation
- Sam Harris and David Deutsch’s second conversation
In this article in Nautilus, where Deustch explains falliblism, he also unpacks why the understanding that we are all fallible isn’t, itself an infallible claim.
Naval Ravikant’s multi-episode podcast about The Beginning of Infinity is an excellent introduction and extension of Deustch’s ideas by two brilliant and passionate students of his work!