 Twardowski's aim is to defend this claim against those who argue that truth is relative on the basis of examples of elliptical sentences (such as ‘I don't’), sentences with indexicals (‘my father is called Vincent’), sentences of general form (‘radioactivity is good for you’), and sentences about ethical principles (‘it is wrong to speak against one's own convictions’). Those who argue that truth is relative on this basis, says Twardowski, make a mistake. They confuse judgments, which are the real truth-bearers, with the (type) sentences expressing them. But sentences are merely the external expression of judgments, and often they do not express everything one has in mind when judging. For human speech has a purely practical task; it can perfectly serve its communicative purposes and yet be strictly speaking ambiguous or elliptic.