Acting on Knowledge

1. Analogies between knowledge and action Knowledge and its Limits starts its exposition of the knowledge-first approach to epistemology with a structural analogy between knowledge and action as the two key relations between mind and world (Williamson 2000, pp. 1, 6-8). The aim of this chapter is to reconsider the relation between knowledge and action, and refine the analogy. 2 Consider the opposition between knowledge-first and belief-first epistemology. The former starts with the distinction between knowledge and ignorance, the latter with the distinction between belief and its absence — typically with a further distinction of belief into justified and unjustified, and perhaps another into degrees of belief. On a popular view in the philosophy of mind, the core of all intentional mental life is 'belief-desire psychology'. Belief and desire are paired. Typically, they are understood as propositional attitudes with opposite directions of fit (Humberstone 1992). With belief we are supposed to fit the mind to the world, with desire to fit the world to the mind. In Anscombe's famous comparison, the shopper tries to fit his purchases to his shopping list, while the detective shadowing him tries to fit her list to his purchases (1957: 56). Belief and desire are supposed to be mirror images, in a mirror that reverses direction of fit. Thus it is 2 natural to ask: what stands to desire as knowledge stands to belief? When all goes well in fitting the mind to the world, there is knowledge. Therefore, what stands to desire as knowledge stands to belief should presumably be what there is when all goes well in fitting the world to the mind. For example, contrast believing that the window is open with desiring that the window be open. In a simple case of knowing that the window is open, one believes that the window is open because the window is open. In a simple case with the reverse direction of fit, the window is open because one desires that the window be open. One intentionally brought it about that the window is open, for instance by opening it or asking someone else to do so. Intentionally bringing something about is what there is when all goes well in fitting the world to the mind. In that sense, action is what stands to desire as knowledge stands to belief. Here and henceforth, 'action' is to be read as 'intentional action'; eating is acting …