Are Propositions Essentially Representational?

Jeffrey King argues that nothing has truth conditions except by being taken to be true or false by rational agents. But – for good reason – King claims that propositions possess truth conditions essentially and intrinsically. I will argue that King cannot have both: if the truth conditions of a proposition depend on the reactions of rational agents, then the possession of truth conditions can't follow from the intrinsic nature or existence of the proposition. This leaves two options. Either, nothing can do the job that motivates positing propositions. Or, there is no need to explain what bestows a truth condition on a proposition.     

Unity and the Frege–Geach problem

The problem of the unity of the proposition asks what binds together the constituents of a proposition into a fully formed proposition that provides truth conditions for the assertoric sentence that expresses it, rather than merely a set of objects. Hanks’ solution is to reject the traditional distinction between content and force. If his theory is successful, then there is a plausible extension of it that readily solves the Frege–Geach problem for normative propositions. Unfortunately Hanks’ theory isn’t successful, but it does point to significant connections between expressivism, unity, and embedding.     

Sharing and Confronting Propositions in Collaborative Inquiry Learning

This study investigates how collaborative knowledge construction within an inquiry learning environment can be assisted with scaffolds that aim to support students' hypothesis generation process. Sixty-six students on a university preparatory track worked collaboratively on a kinematics task. The instructional goal was to develop students' understanding of one-dimensional kinematics. All students completed a proposition test in which they indicated their individual opinions about the truth-value of specific propositions. Subsequently, students were coupled into dyads and assigned to one of three conditions: (a) a shared proposition scratchpad (expression builder), (b) a shared proposition table, and (c) a control condition. Students in the scratchpad condition were given an expression builder consisting of dropdown menus with pre-defined variables and relations. Students in the shared proposition table condition could combine individual opinions about the truth-value of a proposition into one shared proposition table that highlighted differences in opinion. Students in the control condition received no extra support related to propositions. Learning outcomes were assessed using a variety of pre- and posttests. The findings indicate that students supported with the shared proposition table showed significant gains for qualitative knowledge about relations. The number of unique propositions students discussed during the learning session was a significant predictor of learning gains. A more detailed analysis of students' interaction protocols suggests that students differed in their task perceptions, their interaction patterns, and their use of prior knowledge.     

Coherence and Truth: A Cognitive Model of Propositional Truth Attribution

The truth value assigned to a proposition is treated by philosophers, logicians, and most psychologists as an abstract construct, a theoretical object outside the cognitive system. Breaking away from this consensus, we propose to carry out a psychological investigation to analyse the objective, verifiable properties of representations categorized as true by human individuals. We shall reject the conception whereby attributing a truth value to a proposition is the result of the activation of knowledge about the truth of that proposition. We shall also exclude the conception of truth as the result of the establishment of a correspondence with the world. We propose that truth be understood as the result of a decision about the values taken on by the conditions for fulfilment of the act of referencing in a mental model. Our cognitive model of propositional truth attribution is built on the assumption that the truth value of a proposition is determined by the ability of that proposition to fit into the theory of the field to which it refers. This attribution is viewed as a two-stage cognitive activity. During the first stage, the features defining the coherence of the proposition in the activated mental model determine its plausibility value. This defines a generally inconsistent set of truth candidates. The second stage involves selecting the subset containing all propositions which, in context, will be considered true. Two selection criteria are used: maximum consistency and connectivity. The preliminary experimental results proved to be compatible with the proposed model.     

Completing visual contours: the relationship between relatability and minimizing inflections.

Visual completion is a ubiquitous phenomenon: Human vision often constructs contours and surfaces in regions that have no sharp gradients in any image property. When does human vision interpolate a contour between a given pair of luminance-defined edges? Two different answers have been proposed: relatability and minimizing inflections. We state and prove a proposition that links these two proposals by showing that, under appropriate conditions, relatability is mathematically equivalent to the existence of a smooth curve with no inflection points that interpolates between the two edges. The proposition thus provides a set of necessary and sufficient conditions for two edges to be relatable. On the basis of these conditions, we suggest a way to extend the definition of relatability (1) to include the role of genericity, and (2) to extend the current all-or-none character of relatability to a graded measure that can track the gradedness in psychophysical data.     

Completing visual contours: The relationship between relatability and minimizing inflections

Visual completion is a ubiquitous phenomenon: Human vision often constructs contours and surfaces in regions that have no sharp gradients in any image property. When does human vision interpolate a contour between a given pair of luminance-defined edges? Two different answers have been proposed: relatability and minimizing inflections. We state and prove a proposition that links these two proposals by showing that, under appropriate conditions, relatability is mathematically equivalent to the existence of a smooth curve with no inflection points that interpolates between the two edges. The proposition thus provides a set of necessary and sufficient conditions for two edges to be relatable. On the basis of these conditions, we suggest a way to extend the definition of relatability (1) to include the role of genericity, and (2) to extend the current all-or-none character of relatability to a graded measure that can track the gradedness in psychophysical data.     

The representation of time and location in memory for sentences

Two theoretical approaches to the representation of Time and Location Markers in Memory were contrasted. According to predictions derived from one approach, the amount of forgetting will be the same for two-proposition sentences and sentences with a single proposition and a Time or a Location marker. According to the other approach, the amount of forgetting will be the same for one-proposition sentences and sentences with a Time or a Location Marker. Propositional structure and the level of within-sentence associations were orthogonally varied to create eight within-subject experimental conditions. Ninety subjects studied 40 sentences and were required to recall then. Four dependent variables were used: number of sentences completely recalled, number of sentences partially recalled, number of sentences where information was lost from within the proposition, and number of sentences where a complete proposition was lost. The results suggest that Time and Location markers are represented in memory as arguments in a proposition rather than as separate propositions. Level of associations within the sentence seems to have a different effect when the sentence is composed of one or two propositions. The results also suggest that there may be differences between the representations of Time and Location markers.     

The recall and use of belief statements as bases for judgments: Some determinants and implications

When people are asked to report their beliefs in a (target) statement, they may search memory for other, “informational” propositions that bear on its validity, and may use their beliefs in these propositions as bases for their judgments. Several factors were hypothesized to affect the particular propositions that subjects are likely to recall under such conditions. Subjects first familiarized themselves with a list of informational and target propositions. Then, they reported either their beliefs in these propositions or their attitudes toward them. In a second session 1 week later, they recalled as many of the propositions as they could. Both informational and target statements were better recalled when the informational propositions were unlikely to be true. In addition, the target statements were better recalled when the informational propositions associated with them had unclear implications for their validity. Recall of one proposition was more likely to cue the recall of the other when subjects had previously reported belief in the target proposition (rather than attitudes toward it). However, it was more likely to occur when subjects had reported attitudes toward the informational proposition (rather than beliefs in it). The effects of these variables were interpreted in terms of their mediating influence on the strength of association between the informational proposition and both (a) the target proposition and (b) contextual and environmental cues in the situation where target beliefs are reported.     

Theism and other minds: On the falsifiability of non-theories

In this paper I consider three necessary conditions for a proposition counting as a theory: that the proposition be posited for its explanatory power; that it derive its feasibility from the extent to which it provides such explanatory power; and that it be empirically falsifiable. I then argue that some propositions might fail as theories because they do not satisfy the first two conditions, yet still satisfy the third condition. Such propositions I label falsifiable non-theories. I offer folk psychology (the proposition that beliefs, desires, and other intentional phenomena exist and play essential motivational and causal roles in many human actions) as a paradigm example of a falsifiable non-theory. I then argue that theism is in an analogous position. Like folk psychology, it fails to satisfy the first two conditions above for most theists. However, the empirical implications that theism has do make it susceptible to falsification. I demonstrate such falsifiability by an extreme scenario from Keith Yandell. Then I argue that recent work by Paul Draper demonstrates how a well articulated empirical argument from evil might threaten just such falsification.     

Unenriched Subsentential Illocutions*

In this paper I challenge the common wisdom (see Dummett and Davidson) that sentences are the minimal units with which one can perform a speech act or make a move in the language game. I thus sit with Perry and Stainton in arguing that subsentences can be used to perform full‐fledged speech acts. In my discussion I assume the traditional framework which distinguishes between the proposition expressed and the thought or mental state (possibly a sentence in Mentalese) one comes to grasp when using/understanding an utterance (or sentence‐in‐a‐context) expressing a proposition. Unlike Stainton, I will argue that the proposition expressed by a subsentential assertion and its corresponding thought are not the end product of a pragmatic process of free enrichment. I shall defend the view that a thought may concern something without the thinker having to represent that very thing. This should help us to resist the view that with the utterance of a subsentence enrichment is mandatory. I will further argue that subsentences and their corresponding thoughts are situated. Because of that we can successfully interact and engage in joint ventures using subsentences and be guided by thoughts without having to enrich them. The fact that the actors’ unenriched thoughts are co‐situated may suffice to explain the positive outcome of their joint project. Last but not least, I will also show how the picture I propose gains further support by taking on board Perry’s distinction between reflexive truth conditions and incremental truth conditions (or official content). Since competent speakers can grasp an utterance’s reflexive truth conditions without having to grasp its official content (roughly, the proposition expressed) they can successfully interact without their thoughts having to undergo a process of free enrichment. Moreover, if I’m right in arguing that an utterance’s reflexive truth conditions are the best tool to classify the semantic features of one’s mental state (or sentence in Mentalese), we can further explain mental causation and linguistic communication without appealing to free enrichment.     

复合命题理解能力的发展

采用命题-图形匹配实验法,探讨了儿童、少年和青年人三个阶段的5种类型复合命题理解能力的发展.结果表明:(1)随着年龄增长,复合命题理解能力迅速提高;(2)对复合命题理解的难易,决定于构建的心理模型的数目.理解能力的发展根据心理模型的类型呈现不同的步调,单模型命题的理解在小学阶段已经很好地获得发展,双模型命题则在初中阶段获得较好的发展,三模型命题发展较迟,直至成年仍需发展.     

IS NONDEFECTIVELY JUSTIFIED TRUE BELIEF KNOWLEDGE?

The traditional conception of knowledge as justified true belief is refuted in two famous counterexamples by Edmund L. Gettier. Roderick M. Chisholm has attempted to rescue a version of the traditional conception by distinguishing between defective and nondefective kinds of justification, and redefining knowledge more specifically as nondefectively justified true belief. Chisholm's revised definition avoids Gettier's counterexamples, but goes too far in the opposite direction, imposing conditions that are too narrow and not jointly necessary for knowledge. Chisholm's definition excludes some claims that intuitively constitute genuine knowledge¹ by entailing that if a true belief is invalidated as knowledge when defectively justified by a total body of evidence that also makes evident at least one false proposition, then no knowledge whatsoever can be supported by the same evidence. An alternative analysis of knowledge is proposed, according to which the potential loophole between the state of affairs that justifies belief in a proposition, and the state of affairs that makes the proposition true, permitted by the traditional concept of knowledge and discovered by Gettier's counterexamples, is closed by redefining knowledge as semantically-epistemically evidentially relevant justified true belief.     

Field's Paradox and Its Medieval Solution

Hartry Field's revised logic for the theory of truth in his new book, Saving Truth from Paradox, seeking to preserve Tarski's T-scheme, does not admit a full theory of negation. In response, Crispin Wright proposed that the negation of a proposition is the proposition saying that some proposition inconsistent with the first is true. For this to work, we have to show that this proposition is entailed by any proposition incompatible with the first, that is, that it is the weakest proposition incompatible with the proposition whose negation it should be. To show that his proposal gave a full intuitionist theory of negation, Wright appealed to two principles, about incompatibility and entailment, and using them Field formulated a paradox of validity (or more precisely, of inconsistency).

The medieval mathematician, theologian and logician, Thomas Bradwardine, writing in the fourteenth century, proposed a solution to the paradoxes of truth which does not require any revision of logic. The key principle behind Bradwardine's solution is a pluralist doctrine of meaning, or signification, that propositions can mean more than they explicitly say. In particular, he proposed that signification is closed under entailment. In light of this, Bradwardine revised the truth-rules, in particular, refining the T-scheme, so that a proposition is true only if everything that it signifies obtains. Thereby, he was able to show that any proposition which signifies that it itself is false, also signifies that it is true, and consequently is false and not true. I show that Bradwardine's solution is also able to deal with Field's paradox and others of a similar nature. Hence Field's logical revisions are unnecessary to save truth from paradox.     

Cohérence et vérité. Le rôle des modalisateurs épistémiques dans l'établissement de la vérité propositionnelle

We proposed that the condition truth be understood as the result of a decision about the values taken on by the conditions for fulfilment of the act of referencing in a mental model. Our cognitive model of propositional truth attribution (Baudet, Jhean-Larose, & Legros, 1994) is built on the assumption that the truth value of a proposition is determined by the ability of that proposition to fit into the theory of the field to which it refers. The experimental results proved to be compatible with the proposed model. They validate the first phase of our model: the selection of incoherent subset of truth candidates. This selection is operated thanks to the attribution of plausibility value. This value is determined by explicit index of the pledging of the sender as for the truth of proposals contained in the text sentences. According to these results, the epistemic modalisers of the type “I know” and the type “I believe”, commit the transmitter in different ways as to the truth of propositions. They determine degrees of plausibility and relative coherence between assertions and the mental model in operation. The main function of the enunciation operators such as “I know” in a text, is:

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DO I HAVE TO BE HERE NOW?

Kaplan claims that (1) ‘I am here now’, though analytic, is not a necessary truth. But this sentence is not a proposition, in a sense of proposition in which some, but not all, sentences are propositions. Since it is not a proposition, it is not true, and consequently not analytic. It is in fact a fragment of a proposition, the same fragment as ‘he was there then’ in (2) ‘CJFW said in Oxford on 23 September 1991 that he was there then’. Sentences containing indexicals in general owe their sense to the corresponding fragments of sentences containing ‘quasi-indexicals’(‘then’, for example, is the quasi-indexical to ‘now’ as indexical). Someone uttering (1) assertively will thereby make a proposition like (2) true. (2) entails (3) ‘CJFW said in Oxford on 23 September 1993 that CJFW was in Oxford on 23 September 1991′. So by uttering (1) in the appropriate circumstances I made it true that I had asserted the proposition (4) ‘CJFW was in Oxford on 23 September 1991′. What is analytic and necessarily true is the proposition ‘If (3) then (4)’.     

Relative truth and the first person

In recent work on context-dependency, it has been argued that certain types of sentences give rise to a notion of relative truth. In particular, sentences containing predicates of personal taste and moral or aesthetic evaluation as well as epistemic modals are held to express a proposition (relative to a context of use) which is true or false not only relative to a world of evaluation, but other parameters as well, such as standards of taste or knowledge or an agent. I will argue that the sentences that apparently give rise to relative truth should be understood by relating them in a certain way to the first person. More precisely, such sentences express what I will call ‘first-person-based genericity’, a form of generalization that is based on an essential first-person application of the predicate. The account differs from standard relative truth account in crucial respects: it is not the truth of the proposition expressed that is relative to the first person; the proposition expressed by a sentence with a predicate of taste rather has absolute truth conditions. Instead it is the propositional content itself that requires a first-personal cognitive access whenever it is entertained. This account, I will argue, avoids a range of problems that standard relative truth theories of the sentences in question face and explains a number of further peculiarities that such sentences display.     

Showing,Analysis and the Truth-Functionality of Logical Necessity in Wittgenstein's Tractatus

This paper aims to explain how the Tractatus attempts to unifylogic by deriving the truth-functionality of logical necessityfrom the thesis that a proposition shows its sense. I first interpret the Tractarian notion of showing as the displaying ofwhat is intrinsic to an expression (or a symbol). Then I argue that, according to theTractatus, the thesis that a proposition shows its sense implies the determinacy of sense, the possibility of the complete elimination of non-primitive symbols, the analyticity thesis and the strong analyticity thesis. The picture theory emerges as what provides the only acceptable account of an elementary proposition, subject to the constraint that a proposition must show its sense. The picture theory and the analyticity thesis then entail the contingency thesis (that an elementary proposition is contingent) and the independence thesis (that elementary propositions are mutually logically independent) which, together with the strong analyticity thesis, imply that all logical propositions are tautologies.     

Lutheran Secularism as a Challenge for Constructive Theology: A Swedish Perspective,a Foucauldian Proposal

In this article the Swedish Lutheran heritage is discussed in relation to its historical connections with secularism. The question is raised whether and how constructive and liberating Lutheran theology can be developed under such conditions. In order to deal with this problem, Michel Foucault's late philosophy of truth and subjectivity is discussed. A proposition is made for a constructive theology that does not retreat from secularism but is critically involved in the secular through an emphasized confidence in God.     

Foley's Threshold View of Belief and The Safety Condition on Knowledge

This paper introduces a new argument against Richard Foley's threshold view of belief. Foley's view is based on the Lockean Thesis (LT) and the Rational Threshold Thesis (RTT). The former thesis is the claim that it is epistemically rational to believe a proposition if and only if it is epistemically rational to have a degree of confidence in that proposition sufficient for belief. The latter thesis is the claim that it is epistemically rational to believe a proposition if and only if it is epistemically rational to have a degree of confidence in that proposition that meets or exceeds a specified threshold. The argument introduced here shows that the views derived from the joint endorsement of the LT and the RTT violate the safety condition on knowledge in way that threatens the LT and/or the RTT.