 A first crucial distinction is between a linguistic and an ontological thesis. The linguistic thesis is, roughly, that already expressed above, according to which utterances of sentences of the discourse are best seen not as efforts to say what is literally true, but as useful fictions of some sort. The ontological thesis, by contrast, is the thesis that the entities characteristic of the discourse do not exist, or have the ontological status of fictional entities. One can in principle embrace the linguistic thesis without embracing the ontological thesis, and vice versa.