Perceptual Decision-Making and Beyond: Intention as Mental Imagery

Abstract

The standard view in the philosophy of action is the Causal Theory of Action (cta).1 On this view, a behavioural item counts as an intentional action if and only if it is caused by the appropriate sorts of mental states in the right kind of way. On most popular contemporary accounts (e.g. Searle 1983; Bratman 1987; Mele 1992; Pacherie 2008), the appropriate sort of mental state is an intention, with the intention construed as an attitude towards a proposition. The “right kind of way” is thought to be one in which the content of the intention propagates from an abstract level of description (e.g. the intention to investigate a noise) through to more fine-grained specifications that give a bodily movement a rational structure at the moment of bodily movement (e.g. the intention to switch on this light), and finally culminating in motor commands required to execute the right bodily movements. These levels of abstraction respectively correspond to so-called distal intention, proximal intention, and motor intention. These three kinds of intention have distinct roles in the overall dynamics of intentional action (Pacherie 2008; Mele this volume). In our contribution to this volume we offer an alternative theory of intention, on which it is not a propositional attitude at all but rather a distinct kind of mental imagery. For the purpose of our argument, we can provisionally define a mental image as a quasi-perceptual representation that occurs in the absence of the corresponding stimuli. Such imagery need not be conscious; it can also be unconscious. It may manifest in one or more perceptual modalities (Nanay 2017). The main difference that we wish to mark is that mental imagery has a quasi-perceptual format rather than a quasi-linguistic or propositional one. That idea will be developed in more detail in Sections 1 and 2. Our account is inspired by work in the perceptual decision making literature, where decision is modelled as a process of evidence accumulation under conditions of uncertainty and noise. In the paradigms that are central to this