In Chapter 5 of his book, Res Cogitans (1972), Zeno Vendler argued for the thesis that what we know when we know that p, e.g. that Los Angeles is south of San Francisco, and what we believe when we believe that p cannot be the same despite being expressed in the same words, on the ground that ‘believe’ is what he called a subjective verb and ‘know’ what he called an objective verb. For this he gave two main criteria (1) that subjective verbs can take only ‘subjective that- clauses,’ by which he means clauses which express propositions, whereas objective verbs can take only ‘objective that-clauses,’ by which he means clauses which express facts; (2) that subjective verbs cannot take, whereas objective verbs can take, wh- nominalisations - in practice these are the interrogatives what, who where, when, how - which Vendler also takes as a mark of the objective.