2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/94163Deutsch has recently (in quant-ph/9906015) offered a justification, based only on the non-probabilistic axioms of quantum theory and of classical decision theory, for the use of the standard quantum probability rules. In this note, this justification is examined.LaTeX, 5 pages, no figuresQuantum Physicstext