Scott Alexander uses three fictional stories to illustrate principles of non-empirical scientific reasoning, ultimately applying them to support the many-worlds interpretation of quantum mechanics.

Scott Alexander reviews 'Quantum Computing Since Democritus' by Scott Aaronson, sharing insights gained despite the book's complexity and his own mathematical limitations.

Scott argues that if Big World theories are true and we accept the consequentialist view of identity used by cryonics advocates, then perfect copies of you already exist throughout the multiverse, making cryonics unnecessary for a form of immortality.