What Are Possibilities? Part 5: The Propositional Primitive View

INTRODUCTION

Last week we looked at the Linguistic View (LV) according to which modal properties are characteristics are sentences expressed in a language.  We discovered that the LV has serious problems: (1) its choice of language for constructing “possible worlds” seems arbitrary; and (2) any language it does choose can only describe the world partially, which implies that some facts about the world are not possible simply because a language is unable to express them.

Unlike the LV, the Propositional Primitive View (PPV) prefers to work with propositions instead of sentences. Propositions are distinct from sentences because their meanings transcend specific contexts of use. For example, the English sentence “it is raining” and the French sentence “il pleut” both exist in specific contexts, but they express the same proposition with the same meaning in each case. According to some adherents of the PPV, sameness meaning is evidence that propositions have a transcendent existence, apart from contexts of use. In other words, they exist abstractly rather than concretely. Unlike concrete objects (such as sentences, words, tables, and chairs) that exist in space and time, propositions are abstract objects that occupy a transcendent realm beyond space and time – a realm much like the one envisioned by Plato.

The PPV improves on the LV by making propositions the bearers of modal properties – not sentences. We don’t have to make sense of possible worlds by arbitrarily picking a language because possible worlds are composed of timeless propositions that transcend language. Moreover, modality is not restricted to what languages can express because every fact about the world already has a corresponding proposition that represents it in perfect detail. However, despite these improvements on the LV, the PPV provides very little by way of explaining modality.

THREE MAIN PROBLEMS

First, similar to the LV it presupposes modality rather than explains it. Concepts like consistency, entailment or compossibility are used to explain how possible worlds are composed, but these concepts are modal notions!

Second, how does the PPV ground the possible truth of propositions such as “I am jumping”? The short answer is that this proposition has the modal property of possibility. But that answer is hardly illuminating! It offers no further account of why the proposition has the modal property it does. In reply, advocates of the PPV are forced to conclude that the “having” of a modal property is a primitive relation that can’t be explained any further. Fine. But this conclusion is far from preferable ceteris paribus. Appeals to primitive relations should be a last resort whereas “an account that could say more [by way of explanation] would be preferable theoretically” (Pruss, 1996, pp. 34, 177).

Third, the possible truth of “I am jumping” is more plausibly explained by my abilities as a physical organism, not by the having of a modal property by that proposition. Why? Consider the following thought experiment. Imagine for a moment that the entire Platonic realm of abstract objects suddenly vanished. Propositions would not exist, let alone propositions that have modal properties attached to them. Now if the PPV is true, we would have to conclude that nothing is possible in that scenario because the all abstracta have been removed. But is that so? Does removing the Platonic realm delete the possibility of my jumping? It seems not, and the reason for this is straightforward: abstract objects are causally impotent and therefore irrelevant to whether I can jump. That possibility is best explained by my abilities as a physical organism and by the constraints placed on them. I can jump because my shoes are not stapled to the floor; because my leg muscles are functioning properly and the ceiling is higher than my head, etc, etc. At least in this case, the existence of concrete abilities explains what is possible for me, not a Platonic realm. [For a more detailed account of how and when concrete things provide better grounds for possibilities than abstracta, see Alex Pruss (2011), pp.168-9.]

One thought on “What Are Possibilities? Part 5: The Propositional Primitive View”

Leave a Reply

Your email address will not be published. Required fields are marked *