The Fabric of Reality: The Science of Parallel Universes--and Its Implications

In fact, burning fuel is only one of many things a spaceship has to do to accomplish its real purpose, which is to transport its payload from one point in space to another.

The oracle only predicts the outcomes of experiments. Therefore, in order to use it at all we must first know what experiments to ask it about.

For even in purely practical applications, the explanatory power of a theory is paramount and its predictive power only supplementary.

understanding is one of the higher functions of the human mind and brain, and a unique one. Many other physical systems, such as animals’ brains, computers and other machines, can assimilate facts and act upon them. But at present we know of nothing that is capable of understanding an explanation – or of wanting one in the first place – other than

Quantum theory is, as I have said, one such theory. But the other three main strands of explanation through which we seek to understand the fabric of reality are all ‘high level’ from the point of view of quantum physics. They are the theory of evolution (primarily the evolution of living organisms), epistemology (the theory of knowledge) and the t

So when a cosmic-ray particle strikes a DNA strand and causes a mutation, some of its counterparts in other universes are missing their copies of the DNA strand altogether, while others are striking it at different positions, and hence causing different mutations. Thus a single cosmic-ray strike on a single DNA molecule will in general cause a larg

We understand the fabric of reality only by understanding theories that explain it.

The purpose of high-level sciences is to enable us to understand emergent phenomena, of which the most important are, as we shall see, life, thought and computation.

that is physically special. Within one universe it looks irregular; across universes it has a regular structure, like a crystal in the multiverse.