Rotblat asked himself why other scientists did not make the same decision: why did they not leave? For some of them, scientific curiosity was paramount. They wanted to know whether the theoretical predictions would turn out to be true. Others believed that the work should continue, on the grounds that many American lives would be saved if the weapon was used to bring about a rapid end to the war with Japan. Some agreed that the work should have ceased when it became clear that Germany had abandoned work, but they feared that entertaining this view or acting on it could harm their future career.

Martin Underwood, Joseph Rotblat: a man of conscience in the nuclear age, Brighton [England] ; Portland, Or, 2009, p. 29