 Though some model what is ultimate, others object to the entire project of modeling it. There are three main kinds of concerns in the literature: about the existence of ultimacy, about the coherence of the very idea of ultimacy, and about whether talk and knowledge of ultimacy is humanly possible, even assuming the idea is coherent. The first concern is motivational: for those who think there is nothing ultimate, there seems no point worrying about how it has been conceived. However, as indicated in  Section 1.3,  it is invalid to conclude that there is nothing ultimate without having some sense of the range of what it might be. So even those who think there is nothing ultimate are thrown into the project of modeling it—at least enough to license the conclusion that this work is not worth doing.