David Deutsch Books

The difference between knowledge and mere assertion begins with explanation. Deutsch argues that a good explanation is not just one that fits the facts; it is one that is hard to vary while still accounting for what it explains. In other words, the best explanations are constrained by reality. You c...

From The Beginning of Infinity

Optimism, in Deutsch’s sense, is not positive thinking. It is the belief that problems are inevitable but solvable. That distinction matters because many people confuse optimism with complacency. Deutsch argues the opposite: real optimism is a commitment to criticism, creativity, and improvement. Ci...

From The Beginning of Infinity

Some ideas do more than solve a local problem; they become universal. Deutsch is fascinated by moments when systems cross a threshold and gain the ability to generate unbounded variety. Human language is one example. A finite vocabulary and grammar allow us to express an effectively unlimited range ...

From The Beginning of Infinity

Not everything real is tangible. Deutsch argues that abstractions—such as mathematical truths, political institutions, explanatory theories, and even software—are real in the sense that they have causal power and must be taken seriously in our explanations of the world. A nation is not a physical ob...

From The Beginning of Infinity

Reality is often stranger than common sense allows. In discussing quantum theory, Deutsch defends the many-worlds interpretation and argues that we should take our best explanations seriously, even when they conflict with intuitive pictures of reality. Quantum phenomena cannot be fully understood th...

From The Beginning of Infinity

Knowledge grows through a process much like biological evolution: variation and selection. Deutsch argues that ideas are created, criticized, tested, and improved in an ongoing cycle. In biology, genes vary and environments select. In human thought, conjectures vary and criticism selects. This paral...

From The Beginning of Infinity