Stephen Mumford (University of Nottingham)

Modelling Causes as Vectors

Causal transactions are standardly modelled in neuron diagrams, which are presented as a philosophically neutral way of representing what happens when one thing causes another. It is argued in this paper that neuron diagrams are a theory-laden representation of causation and that the commitments contained are questionable. Instead, a vector model of causation is introduced and developed that shows better the complexity that can be involved in causation. Among other things, the model will allow us to see a solution to the problem of causation by absence.

Session 2 12 January 2025

Célia Teixeira (Centro de Filosofia da Universidade de Lisboa, LanCog Group)

A Priority and Revisability

One very popular reason to claim that a priori knowledge is not possible results from the acceptance of the following thesis: (RT) Nothing is immune to revision. This thesis was famously advocated by W. V. Quine and is still popular among many naturalist philosophers. Someone who claims that if (RT) is true then there is no a priori is implicitly assuming the following thesis: (UAP) If S’s belief that p is justified a priori, then p is unrevisable. And if both (RT) and (UAP) are true, it follows that there is no a priori knowledge. In order to reject this argument against the a priori all we need to do is to show either that (RT) is false or (UAP) is false. My aim is to do just that. More precisely, I will claim that even if (RT) is true, there are no reasons to accept (UAP). In other words, even if nothing is immune to revision, a priori knowledge is still possible.

Session 1 8 January 2025

Teresa Marques (Centro de Filosofia da Universidade de Lisboa, LanCog Group, Universidade de Barcelona, LOGOS Group)

Relativism and the Norm of Assertion

In the recent debate on relativism, John MacFarlane offers the most radical challenge against non relative truth, and, in relation to this, to classical conceptions of assertion and its norm. MacFarlane rightly dismisses truth relative to circumstances of evaluation as a proper variety of relativism, and also rightly criticizes attempts to capture a sense of faultless disagreement by means of circumstance relative truth. In alternative, he proposes that truth should be relativized to contexts or points of assessment, that is, perspectives from which a given previous utterance made at a context of utterance can be evaluated as true or false. Relativistic contents of utterance are those whose truth-value can vary with respect to distinct contexts of assessment, keeping fixed the context at which they were expressed as well as the circumstances with respect to which these contents are evaluated. This challenges the idea of the absoluteness of utterance truth, i.e., the idea that the truth-value of an utterance is independent from the context from which the utterance is being assessed. Now, a challenge to the coherence of this idea was already formulated by Gareth Evans. Given what speakers aim at in making assertions, and a weak enough norm of assertion such as the truth norm - assert only what is true (we do not need to consider stronger norms such as the knowledge norm), if utterance truth were relative to the assessment of different possible evaluators’ perspectives, then speakers could not be responsible for failing to speak the truth. Speakers can aim at, and be held responsible for, attaining the truth norm, if doing so is somehow within their powers. If MacFarlane is right, however, there is an insurmountable gap between the eventual truth of a speaker’s utterance, and the speaker’s own commitment, and responsibility, with the truth of his utterance. MacFarlane takes up the challenge set by Evans and proposes that utterance relative truth is compatible with a distinct and, he claims, plausible alternative norm of assertion. I argue that MacFarlane’s new norm (let us call it the meet-the-challenge norm), is as impossible to meet as the more standard truth norm. In other words, speakers are no more obliged and responsible to face any challenge whatsoever to the truth of their utterances, from any context of assessment, than they are to meet the truth norm, if utterance truth is relative to contexts of assessment. (similar problems would arise for other speech acts). The problem is general. Norm regulated acts allow us to distinguish between, on the one hand, an act being correct or incorrect, and an agent’s responsibility and accountability in meeting the norm. Norms are, in general, something agents can meet and, because of this, by which they can be judged and held responsible. This gives us a reason, although not a conclusive one, against norms which cannot be met, and, in the relativism debate, against relative truth as in MacFarlane’s proposal.