Greg Egan’s Sleep and the Soul collects his very newest short-form work: nine stories originally published between 2019 and 2022, plus one that is, as of this writing, not even officially out yet. This is the seventh collection of Egan’s short work I have reviewed over nearly three decades, and I notice (again) how he demonstrates one of the fundamental generating mechanisms of science fiction: what Samuel Delany (and then Joanna Russ) called ‘‘subjunctivity,’’ the posing and elaborating of the conjectural what-ifs that generate enabling devices and story possibilities – the raw materials of ‘‘worldbuilding.’'(Introduction)