 The suggestion was that even apparently tautologous sentences, like ‘Bachelors are unmarried’ and ‘Caesar died if Brutus killed him’, have empirical content. These may be among the last sentences we would dissent from, faced with recalcitrant experience; we may prefer to say that Caesar didn’t really die, or that Brutus didn’t really kill him, if the next best alternative is to deny the conditional claim. But for Quine, every meaningful claim is a claim that could turn out to be false—and so a claim we must be prepared, at least in principle, to reject. Correlatively, no sentences are known to be true simply by knowing what they mean and knowing a priori that sentences with such meanings must be true.