Indicative vs Subjunctive Conditionals

Ordinary speakers intuitively assign truth-values to conditional utterances in everyday conversation, but, despite the general ease with which this occurs, it is notoriously difficult to give an account of the implicit logic that is followed in making these truth-value assignments. I propose a twofold logic of the conditional – a relatively simple “factual” logic for conditionals interpreted with regard to what is actually the case, largely following the logic of the material conditional; combined with a variably strict possible-worlds counterfactual logic (...) for conditionals interpreted with regard to with what may be (or may have been) the case, incorporating a ceteris paribus clause. This theory is able to deal with a number of challenges for other prominent views of the conditional, such as counter-intuitive truth-value ascriptions provided by notions of similarity or closeness, and difficulties adequately accounting for phenomena such as reverse Sobel sequences. (shrink)

This paper is a guide to the main ideas and innovations in Robert Stalnaker's "Indicative Conditionals". The paper is for a volume of essays on twenty-one classics of formal semantics edited by Louise McNally, Yael Sharvit and Zoltàn Gendler Szabò.

This is a handbook article about conditionals.

A part of Stalnaker (1968)’s influential theory of conditionals has been neglected, namely the role for an accessibility relation between worlds. I argue that the accessibility relation does not play the role intended for it in the theory as stated, and propose a minimal revision which solves the problem, and brings the theory in line with the formulation in Stalnaker & Thomason 1970.

The purpose of this note is to dispute Michael Ayers' claim that "there is no special problem of subjunctive conditionals".

Practical deliberation often involves conditional judgements about what will (likely) happen if certain alternatives are pursued. It is widely assumed that the conditionals useful in deliberation are counterfactual or subjunctive conditionals. Against this, I argue that the conditionals of deliberation are indicatives. Key to the argument is an account of the relation between 'straightforward' future-directed conditionals like ' If the house is not painted, it will soon look quite shabby' and * "w e r e ' ' e d F (...) D C s like ' If the house were not to be painted, it would soon look quite shabby': an account on which both of these types of FDCs are grouped with the indicatives for semantic treatment and on which, while conditionals of both types are properly used in means/ends deliberations, those of the ' were'ed-up variety are especially well suited for that purpose. (shrink)

I give cases where the contrast between "if Shakespeare had not written Hamlet someone else would have" and "if Shakespeare did not write Hamlet and someone else did"is found in future tense sentences. This is often denied.

At the center of the literature on conditionals lies the division between indicative and subjunctive conditionals, and Ernest Adams’ famous minimal pair: If Oswald didn’t shoot Kennedy, someone else did. If Oswald hadn’t shot Kennedy, someone else would have. While a lot of attention is paid to figuring out what these different kinds of conditionals mean, significantly less attention has been paid to the question of why their grammatical differences give rise to their semantic differences. In this paper, I articulate (...) and defend an answer to this question that illuminates and unifies the meanings of both kinds of conditionals. The basic idea is that epistemic and metaphysical possibilities differ with respect to their interaction with time, such that there can be present epistemic possibilities with different pasts, while present metaphysical possibilities share the same past. The interpretation of conditionals is subject to a pragmatic constraint that rules out interpretations in which their consequents are directly settled by information used to build their domains. The past + future morphology on subjunctives, but not indicatives, is what allows them to receive a metaphysical interpretation in light of this pragmatic constraint. The resulting theory predicts several surprising features of indicatives and subjunctives, which I argue are correct. (shrink)

A few purported counterexamples to the Adams thesis have cropped up in the literature in the last few decades. I propose a theory that accounts for them, in a way that makes the connections between indicative conditionals and counterfactuals clearer.

The commonplaces, all grammatically confused, are that ?conditionals? are ternary in structure, have ?antecedents? and conform to the traditional taxonomy. It is maintained en route that ?The bough will not break? is consistent with ?If the bough breaks ??, that there is no logical difference between ?future indicatives? and ?subjunctives?, and that there is a difference between the logic of propositions (e.g. ?The bough broke?) and that of judgments (?The bough will/might/could/should/must/needn't break?).

§0. A familiar if obscure idea: an indicative conditional presents its consequent as holding in the actual world on the supposition that its antecedent so holds, whereas a subjunctive conditional merely presents its consequent as holding in a world, typically counterfactual, in which its antecedent holds. Consider this pair.

In "Against the Indicative," AUSTRALASIAN JOURNAL OF PHILOSOPHY 72 (1994): 17-26, and more recently in "Classifying `Conditionals': the Traditional Way is Wrong", ANALYSIS 60 (2000): 147, V.H. Dudman argues that (a) `If Oswald didn't shoot Kennedy then someone else did' and (b) `If Oswald doesn't shoot Kennedy then someone else will' should not be classified together as "indicative conditionals." Dudman relies on the assumption that (a) is entailed by (c) `Someone shot Kennedy', whereas (b) is not entailed by (d) `Someone (...) will shoot Kennedy'. I argue that the same reasoning which shows that (d) does not entail (b) also shows that (c) does not entail (a). One upshot is that Dudman's and Mellor's respective interpretations of so-called past indicative conditionals cannot be correct. (shrink)

Against Barnett (2012), I argue that the theory I advance in DeRose 2010 is best construed as one on which ‘"were"ed-up’ future-directed conditionals like ‘If the house were not to be painted, it would soon look quite shabby’ are, in ways important to how they function in deliberation, different in literal content from their ‘straightforward’ counterparts like ‘If the house is not painted, it will soon look quite shabby’. I also defend my way of classifying future-directed conditionals against an attack (...) by Barnett by defending a standard (among philosophers) approach to the basic structure of some conditionals. Finally, I counter Barnett’s charge that by using the concept of deliberation in my account of the meaning of future-directed conditionals, I put an implausibly demanding constraint on what it takes to understand such sentences. (shrink)

Practical deliberation often involves conditional judgements about what will happen if certain alternatives are pursued. It is widely assumed that the conditionals useful in deliberation are counterfactual or subjunctive conditionals. Against this, I argue that the conditionals of deliberation are indicatives. Key to the argument is an account of the relation between ‘straightforward’ future-directed conditionals like ‘If the house is not painted, it will soon look quite shabby’ and ‘ “were”ed-up’ FDCs like ‘If the house were not to be painted, (...) it would soon look quite shabby’: an account on which both of these types of FDCs are grouped with the indicatives for semantic treatment and on which, while conditionals of both types are properly used in means/ends deliberations, those of the ‘were’ed-up variety are especially well suited for that purpose. (shrink)

A uniform theory of conditionals is one which compositionally captures the behavior of both indicative and subjunctive conditionals without positing ambiguities. This paper raises new problems for the closest thing to a uniform analysis in the literature (Stalnaker, Philosophia, 5, 269–286 (1975)) and develops a new theory which solves them. I also show that this new analysis provides an improved treatment of three phenomena (the import-export equivalence, reverse Sobel-sequences and disjunctive antecedents). While these results concern central issues in the study (...) of conditionals, broader themes in the philosophy of language and formal semantics are also engaged here. This new analysis exploits a dynamic conception of meaning where the meaning of a symbol is its potential to change an agent’s mental state (or the state of a conversation) rather than being the symbol’s content (e.g. the proposition it expresses). The analysis of conditionals is also built on the idea that the contrast between subjunctive and indicative conditionals parallels a contrast between revising and consistently extending some body of information. (shrink)

In deciding whether to read this paper, it might seem reasonable for you to base your decision on your confidence (i) that, if you read this paper, you will become a better person. It might also seem reasonable for you to base your decision on your confidence (ii) that, if you were to read this paper, you would become a better person. Is there a difference between (i) and (ii)? If so, are you rationally required to base your decision on (...) your confidence in one of the two conditionals, rather than the other? Keith DeRose (2010) proposes a provocative pair of answers to these questions. In this paper, I argue that DeRose’s answers are incorrect, and I defend a rival pair of answers. (shrink)

This paper offers an argument against V. H. Dudman's view about future conditionals.

Conventional wisdom has it that many intriguing features of indicative conditionals aren’t shared by subjunctive conditionals. Subjunctive morphology is common in discussions of wishes and wants, however, and conditionals are commonly used in such discussions as well. As a result such discussions are a good place to look for subjunctive conditionals that exhibit features usually associated with indicatives alone. Here I offer subjunctive versions of J. L. Austin’s ‘biscuit’ conditionals—e.g., “There are biscuits on the sideboard if you want them”—and subjunctive (...) versions of Allan Gibbard’s ‘stand-off’ or ‘Sly Pete’ conditionals, in which speakers with no relevant false beliefs can in the same context felicitously assert conditionals with the same antecedents and contradictory consequents. My cases undercut views according to which the indicative/subjunctive divide marks a great difference in the meaning of conditionals. They also make trouble for treatments of indicative conditionals that cannot readily be generalized to subjunctives. (shrink)

When philosophers and linguists theorize about the nature of conditionals, they tend to make a number of assumptions about the linguistic structure of these sentences. For example, they almost invariably assume that conditionals have “antecedents” and “consequents” and that these have the structure of independent clauses. With a few exceptions, they assume that conditionals are categorized according to whether they are in the “indicative” or the “subjunctive” “mood”. However, rarely do they formulate criteria for identifying these moods, or for distinguishing (...) between indicative and subjunctive conditionals.Through an analysis of the coordinated verb tense structures of the clauses of English conditionals, I challenge these and other related assumptions and show that the one relatively well-developed attempt to provide criteria for distinguishing between indicative and subjunctive conditionals---that of Gibbard (1980)---fails in its task. I then offer an alternative account of the linguistic structure of conditional constructions. To represent their structure I use first-order predicate logic with added devices to indicate deictic and anaphoric reference. (shrink)

Lowe claims that "if oswald did not kill kennedy, someone else did" is a material conditional. he also claims that the difference in truth-value between this indicative conditional and the subjunctive "if oswald had not killed kennedy, someone else would have" does not support the conclusion of lewis and others that corresponding indicative and subjunctive conditionals are not always equivalent. i dispute both claims.

Work in progress. Will probably split into two papers, and then, perhaps, later, will be brought back together, along with other material, into something larger. (All this only if it works out OK!).

I take issue with two claims of DeRose: Conditionals of deliberation must not depend on backtracking grounds. ‘Were’ed-up conditionals coincide with future-directed indicative conditionals; the only difference in their meaning is that they must not depend on backtracking grounds. I use Egan’s counterexamples to causal decision theory to contest the first and an example of backtracking reasoning by David Lewis to contest the second claim. I tentatively outline a rivaling account of ‘were’ed-up conditionals which combines features of the standard analysis (...) of counterfactuals with the contextual relevance of the corresponding indicative conditionals. (shrink)

Nonmonotonic conditionals (A |∼ B) are formalizations of common sense expressions of the form “if A, normally B”. The nonmonotonic conditional is interpreted by a “high” coherent conditional probability, P(B|A) > .5. Two important properties are closely related to the nonmonotonic conditional: First, A |∼ B allows for exceptions. Second, the rules of the nonmonotonic system p guiding A |∼ B allow for withdrawing conclusions in the light of new premises. This study reports a series of three experiments on reasoning (...) with inference rules about nonmonotonic conditionals in the framework of coherence. We investigated the cut, and the right weakening rule of system p. As a critical condition, we investigated basic monotonic properties of classical (monotone) logic, namely monotonicity, transitivity, and contraposition. The results suggest that people reason nonmonotonically rather than monotonically. We propose nonmonotonic reasoning as a competence model of human reasoning. (shrink)

Why are some conditionals subjunctive? It is often assumed that at least one crucial difference is that subjunctive conditionals presuppose that their antecedent is false, that they are counterfactual (Lakoff 1970). The traditional theory has apparently been refuted. Perhaps the clearest counter-example is one given by Alan Anderson (1951: 37): If Jones had taken arsenic, he would have shown just exactly those symptoms which he does in fact show. A typical place to use such a subjunctive conditional would be in (...) the course of an argument that tries to bolster the hypothesis that Jones did in fact take arsenic. But then it would of course be self-defeating to presuppose that the hypothesis is false. Thus, something else must be going on. (shrink)

It is known that indicative and subjunctive conditionals interact differently with a rigidifying "actually" operator. The paper studies this difference in an abstract setting. It does not assume the framework of possible world semantics, characterizing "actually" instead by the type of logically valid formulas to which it gives rise. It is proved that in a language with such features all sentential contexts that are congruential (in the sense that they preserve logical equivalence) are extensional (in the sense that they preserve (...) material equivalence). For a subjunctive conditional, the natural conclusion to draw is that it is non-congruential. It is much harder to defend the claim that an indicative conditional is non-congruential. The pressure to treat the indicative conditional as truth-functional is correspondingly greater. The implications of these results for attempts to interpret the indicative conditional as an epistemic or doxastic operator are assessed. (shrink)

This paper presents a new theory of the truth conditions for indicative conditionals. The theory allows us to give a fairly unified account of the semantics for indicative and subjunctive conditionals, though there remains a distinction between the two classes. Put simply, the idea behind the theory is that the distinction between the indicative and the subjunctive parallels the distinction between the necessary and the a priori. Since that distinction is best understood formally using the resources of two-dimensional modal logic, (...) those resources will be brought to bear on the logic of conditionals. (shrink)

David Lewis has argued that there must be a difference between indicative and counterfactual conditionals beyond an indication of truth-value commitments. He cites the following contrast to show this: If Oswald did not shoot Kennedy, then someone else did. If Oswald had not shot Kennedy, then someone else would have. In response, it is shown that this difference is better explained by shifts in context. Keep context fixed, the contrast disappears. EG: If Oswald was not the one who shot Kennedy, (...) then someone else was. If Oswald had not been the one who shot Kennedy, then someone else would have been. (shrink)

Received doctrine has an 'antecedent' message encoded within a conditional clause, such as the string comprising the first five words of the sentence 'If the bough had broken the cradle would have fallen'. Criticisms of mine of this tenet were recently challenged by Stephen Barker. In the course of responding to his examination, I venture a snappy demonstration that the 'conditionals' such sentences encode can have neither 'antecedents' nor 'consequents'. Also, less happily, I urge a binary outermost structure for these (...) conditionals. (shrink)

The idea that english has more than one declarative "mood" has been dismissed as superstitious by empirically-minded grammarians of english for centuries--with such spectacular unsuccess, however, that the indicative/subjunctive dichotomy stands today as a cornerstone for philosophical and logical speculation about "conditionals." let me be next into the breach. i shall urge that there is no grammatical basis for any such distinction. and as for the particular adjudications of mood logicians and philosophers actually propose, there is neither rhyme nor reason (...) to them. my bent, then, is basically destructive. but i shall also be outlining a better taxonomy. (shrink)