Imaginary Foundations

Abstract

Our senses provide us with information about the world, but what exactly do they tell us? I argue that in order to optimally respond to sensory stimulations, an agent's doxastic space may have an extra, "imaginary" dimension of possibility; perceptual experiences confer certainty on propositions in this dimension. To some extent, the resulting picture vindicates the old-fashioned empiricist idea that all empirical knowledge is based on a solid foundation of sense-datum propositions, but it avoids most of the problems traditionally associated with that idea. The proposal might also explain why experiences appear to have a non-physical phenomenal character, even if the world is entirely physical. 1. The conditional probabilities P old (A/E) are often computed via Bayes' Theorem, which is why conditionalization is also known as Bayes' Rule.

Certainty and Our Sense of Acquaintance with Experiences

“…There have been numerous attempts at giving a physico-functional explanation of our sense of acquaintance with experiences. I intend to examine and criticize one particular line of thought, first presented by Wolfgang Schwarz (Schwarz, 2018(Schwarz, , 2019 and endorsed, with some modifications, by Andy Clark, Karl Friston and Sam Wilkinson (Clark et al, 2019). However, before I turn to this line of thought, a few words about other physicalist takes on our sense of acquaintance.…”

“…Because this line of thought, as I interpret it, consists in claiming that the very design of our cognitive systems leads us to hold beliefs about experiences with certainty, I call these views "designed certainty views". 7 Wolfgang Schwarz (Schwarz, 2018(Schwarz, , 2019 originally develops his conception within a Bayesian picturealthough the point I want to discuss can be abstracted from this framework. He suggests that, if we conceive of our cognitive systems as kinds of Bayesian perceivers, which need to update their beliefs upon incoming sensory stimuli, it could be advantageous for our cognitive systems to entertain some absolute certainty towards certain "imaginary" propositions in order to facilitate this process of belief updating.…”

“…A recent promising line of thought has lately been gaining traction (Clark et al, 2019;Schwarz, 2018Schwarz, , 2019. According to this line of thought, our sense that experiences are presented in a peculiarly immediate and revelatory way, itself crucial for our impression that consciousness is 1 I would like to thank the audience at the ANU as well as Wolfgang Schwarz for their comments.…”

Rigidity, symmetry and defeasibility: On Weisberg's puzzle for perceptual justification

“…88Others have presented different formal treatments of Weisberg's puzzle—see, for instance, Gallow (2014) and Schwarz (2018). To my mind, the solution in terms of ur‐priors has the advantage of being up‐front about what is left out of the model, an issue discussed in the next section.…”