 It is an interesting fact that almost alone among terminist logicians, Ockham does not speak of ampliation and restriction. (See Priest and Read 1981.) The reason appears to be that he disagrees with the truth-condition given above for ‘A white thing was black’, and similar cases. This proposition, he says, is ambiguous. Rather than meaning that what is or was white was black, it equivocates between ‘What is white was black’ and ‘What was black was white’: “in the case of every proposition of the past and of the future in which the subject is a general term or a demonstrative pronoun with a general term or a discrete term referring to some composite, we must distinguish [two  senses]”.[31]  Whether Ockham realized that his theory improved on the ampliative theory is unclear; nonetheless, his account seems to accord better with intuition. For the ampliative account is disjunctive: it says that the proposition is true if either what was white was black or what is white was black. Then it is true if either disjunct is true; whereas on Ockham's account it has two different senses, and can be false on one while true on the other – true because something now white used to be black but false if nothing which used to be white was ever black. For a clearer case, take the first sex-change operation – for the first time, say, a woman was a man. But no one who was a woman had ever been a man, so it was (also) false that a woman was a man. The proposition ‘A woman was a man’ is ambiguous and “est distinguenda ” (i.e., different senses must be distinguished, one true, one false).