He begins this speech, which was tape recorded in Cambridge shortly before he died -- he begins by explaining how science works through the testing of hypotheses that are framed to be vulnerable to disproof, and then he goes on.
Comincia il suo discorso, registrato su nastro a Cambridge poco prima che morisse, spiegando come funziona la scienza, attraverso la verifica di ipotesi pronte ad essere confutate in ogni momento.