The source of modal truth

Modality (Theory of knowledge);Necessity (Philosophy)

Cameron, Ross P.

University:University of St Andrews

Department:Philosophical, Anthropological & Film Studies (School of)

关键词: Modality (Theory of knowledge);    Necessity (Philosophy);   

Others  :  https://research-repository.st-andrews.ac.uk/bitstream/handle/10023/10949/RossCameronPhDThesis.pdf?sequence=2&isAllowed=y

来源: DR-NTU

【 摘 要 】

This thesis concerns the source of modal truth. I aim to answer the question: what isit in virtue of which there are truths concerning what must have been the case as amatter of necessity, or could have been the case but isn't.I begin by looking at a dilemma put forward by Simon Blackburn which attempts toshow that any realist answer to this question must fail, and I conclude that either hornof his dilemma can be resisted. I then move on to clarify the nature of thepropositions whose truth I am aiming to find the source of.I distinguish necessity de re from necessity de dicto, and argue for a counterparttheoretic treatment of necessity de re. As a result, I argue that there is no specialproblem concerning the source of de re modal facts. The problem is simply toaccount for what it is in virtue of which there are qualitative ways the world couldhave been, and qualitative ways it couldn't have been.I look at two ways to answer this question: by appealing to truthmakers in the actualworld, or by appealing to non-actual ontology. I develop a theory of truthmakers, butargue that it is unlikely that there are truthmakers for modal truths among theontology of the actual. I look at the main possibilist ontology, David Lewis' modalrealism, but argue that warrant for that ontology is unobtainable, and that weshouldn't admit non-actual possibilia into our ontology.I end by sketching a quasi-conventionalist approach to modality which denies thatthere are modal facts, but nevertheless allows that we can speak truly when we usemodal language.