The Four Strands
In his book, The Fabric of Reality, David Deutsch outlined four fundamental theories that he claimed must be understood together in order to come to a unified view of our reality. While each of these will be explored deeper, here is a short introduction.
The four strands are:
1. Quantum Physics - One of the two fundamental theories of physics (Einstein's theory of relativity being the other). Quantum physics is the deepest and most successful theory of physics and, along with relativity, these theories provide the framework upon which all other theories of physics are expressed today.
2. The Theory of Evolution - This is a theory about emergent properties that explains how large objects can be understood in terms that do not follow from their lower level definitions. Darwin's theory explains rigorously how living organisms evolve, in a way that can never be expressed as a theory of atoms.
3. The Theory of Computation - This explains processes in nature that are independent of and transcend the material substance they are embodied in. Information is abstract but can also be instantiated in a physical structure like a brain. The theory of computation explains how information can be processed and any of the transitions between physical instantiations that can take place.
4. The Theory of Knowledge - Knowledge is essentially the kind of information that can do things or solve problems in human terms. What makes it fundamental is that the vast majority of all physical transformations that are possible in the universe require the right knowledge.
On closer inspection it will become apparent that these theories can only really be understood properly in light of each other. What makes them fundamental is that together they are required in the higher level explanations of most phenomena. They are the basis for our ever broadening, deepening, and more integrated understanding of our reality.
Watch the short video below to see David speak about the four strands.