Jacob VanDrunen

I pose and answer a new skeptical challenge for Christianity: At least sometimes, conversion to Christianity involves acquiring an undesirably high confidence in certain propositions. This acquisition of undesirably high confidence can be represented in formal terms as a violation of the principle of reflection. The novelty of the challenge is fourfold. First, it applies even if Christian belief is warranted. Second, it concerns conversion to Christianity from the agent’s perspective ex ante, rather than Christian belief in the abstract or belief that has already been acquired. Third, it is pragmatic. Fourth, it concerns the axiology (rather than the ethics or the rationality) of belief—that is, whether Christian belief is good or desirable. I suggest a pragmatic solution along the lines of William James’s famous response to W. K. Clifford on the ethics of believing beyond what one’s evidence supports.

Grice, Lewis, and Skyrms proposed similar distinctions between kinds of meaning. The meaning of terms in human language, as Lewis and Skyrms had it, is ‘conventional’. Skyrms presented models showing how it is possible for conventional meaning to evolve in a population without reliance on pre-existing meaning. But one might think of conventionality as coming in degrees, based on whether the evolutionary process begins with ‘natural saliences’. We propose a theory of natural salience and several extensions of Skyrms’s models to capture this notion. These models reveal that natural saliences can hinder, as well as help, the evolution of language.

Signalling games are useful for understanding how language emerges. In the standard models, the dynamics in some sense already know what the signals are, even if they do not yet have meaning. In this article, we relax this assumption and develop a simple model we call an ‘attention game’, in which agents have to learn which feature of their environment is the signal. We demonstrate that simple reinforcement learning agents can still learn to coordinate in contexts where the agents do not already know what the signal is, and the other features in the agents’ environment are uncorrelated with the signal. Furthermore, we show that in cases where other features are correlated with the signal, there is a surprising trade-off between learning what the signal is and success in action. We show that the mutual information between a signal and a feature plays a key role in governing the accuracy and attention of the agent.

Wittgenstein used the notion of a language game to illustrate how language is interwoven with action. Here we consider how successful linguistic discourse of the sort he described might emerge in the context of a self-assembling evolutionary game. More specifically, we consider how discourse and coordinated action might self-assemble in the context of two generalized signaling games. The first game shows how prospective language users might learn to initiate meaningful discourse. The second shows how more subtle varieties of discourse might co-emerge with a meaningful language.