The anatomy of a minimal mind

This thesis is entitled "The Anatomy of a Minimal Mind". By a "minimal mind" I mean the simplest kind of mind that could exist. As there is widespread philosophical disagreement about what a mind is, or what mental states are, I refrain from assuming at the outset that a minimal mind has to be phenomenally conscious, or subjectively aware. 0f events in its surroundings. My objective is to identify the requirements that an organism would have to satisfy, before it could be credited with possessing a mind of any sort, however rudimentary. I then attempt to develop a detailed model of this minimal mind, using a conservative methodological approach: we should not interpret an organism's behaviour as a manifestation of underlying mental states unless doing so enables us to make better scientific predictions about its behaviour and/or explain its behaviour more fully. In section A, chapter one, I discuss the philosophical background to the contemporary discussion of minds and mental states. I defend the controversial claim that only living things can be said to have minds or mental states, and I argue that there are no convincing grounds for rejecting the common view that mental states are real phenomena. This in no way implies the more controversial view that all mental phenomena share some distinguishing feature that characterises them as mental. If, however, there is some distinguishing property which is common to all mental states, and only those states, then the two most promising philosophical candidates for this property would surely be consciousness and intentionality. I argue that the different varieties of consciousness distinguished by philosophers fail to "carve nature at the joints". I then analyse the strengths and weaknesses of three common definitions of intentionality. Lastly, I examine Dennett's intentional stance and argue that the two ways in which it can be formulated are in fact quite distinct. I propose that one of these formulations, which I refer to as the agent-centred intentional stance, can be used to help us identify creatures with minimal minds. In section B (chapters two to eight), I attempt to identify the necessary conditions for intentional agency in creatures, by examining several broad categories of behavioural and biological properties that have been proposed in the philosophical and scientific literature as relevant to having a mind, and sifting through them, all the while attempting to put together a constructive definition of a "minimal mind". In particular, I discuss sensory capacities (including discriminatory ability and perception); memory; flexible behaviour patterns; the ability to learn; self-directed movement and control; the ability to correct one's mistakes; and the ability to form concepts. Within each category of "mind-relevant" properties, I examine the different ways in which these properties are realised by different kinds of organisms, at various levels of complexity. The biological case studies that 1 discuss range from the relatively simple (viruses) to the most complex (vertebrates, especially birds and mammals). In section C, I list about a dozen detailed conditions that an animal has to meet before it can be said to possess this kind of "minimal mind", which, 1 argue, is the most basic kind of mind anything can have. Perhaps the most crucial condition is that the animal possess an internal "minimal map" by which it represents the means it has to adopt to achieve its ends, enabling it to steer itself around its environment. 1 argue that animals whose maps are of the right sort can be said to have beliefs, desires and intentions. Finally, 1 claim that these "minimal minds" come in no less than four different varieties. Operant agency, navigation using visual landmarks, tool use and the social practice of following a guide are all behaviours that manifest mental states. Although these states are not phenomenally conscious states, 1 argue that the intentionality they possess is fundamentally the same as that found in conscious mental states. In the end, I conclude that many insects and spiders, as well as octopuses and squid, and of course fish, qualify as having minimal minds