David Deutsch

David Deutsch is the physicist-philosopher whose case for optimism Kyle threads through two of his essays. In It’s Time To Build… But Build What - Research, Deutsch supplies the closing line of Marc Andreessen’s Techno-Optimist Manifesto: “We have a duty to be optimistic. Because the future is open, not predetermined and therefore cannot just be accepted: we are all responsible for what it holds. Thus it is our duty to fight for a better world.” He anchors the e/acc / Techno-Optimism section of that research as the moral grounding for progress-positivity.

In What’s In a Post-Mortem - Research, Deutsch returns via The Beginning of Infinity and his Principle of Optimism — “all evils are caused by insufficient knowledge” — which Kyle, by way of Packy McCormick’s “Optimism” piece, uses to distinguish real optimism from “happy ears.” Deutsch’s framing is that optimism is “a way of explaining failure, not prophesying success,” and that “there is only one way of making progress: conjecture and criticism.” That conjecture-and-criticism loop maps directly onto the post-mortem discipline the essay argues for.

Context: David Deutsch is a British physicist at Oxford, a pioneer of quantum computation, and the author of The Fabric of Reality and The Beginning of Infinity. His philosophy of knowledge — drawing on Karl Popper — holds that problems are soluble and that progress comes from creating good explanations.

Where this appears

• It’s Time To Build… But Build What - Research — his “we have a duty to be optimistic” line closes Andreessen’s Techno-Optimist Manifesto, used in the e/acc section.
• What’s In a Post-Mortem - Research — The Beginning of Infinity and the Principle of Optimism (“all evils are caused by insufficient knowledge”; “conjecture and criticism”) frame real optimism vs. “happy ears.”
• TED Talks: The Official TED Guide to Public Speaking — The Fabric of Reality’s knowledge-vs-understanding argument is the passage Chris Anderson credits with convincing him to take over TED.