HackerDavid Deutsch: A new way to explain explanation
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Further reading 1
Caption notes
David Deutsch uses seasons to explain what makes details hard to vary. Axial tilt constrains the relation between hemispheres. A story that survives any substitution of characters makes little comparable commitment.
Video or transcript source ↗Original passages · 2
That's a good explanation: hard to vary, because every detail plays a functional role.And the tilt also explains the sun's angle of elevation at different times of year, and predicts that the seasons will be out of phase in the two hemispheres.