Hume Studies

Hume Studies Volume 28, Number 1, April 2002, pp. 27-48 Hume and Reid on the Perception of Hardness LORNE FALKENSTEIN Nicholas Wolterstorff has recently identified what he takes to be a "decisive" argument employed by Reid to refute "Humean phenomenalism."1 The argument turns on appeal to the specific case of our perception of hardness, which according to Wolterstorff could not possibly be accounted for by any theory that holds that all of our knowledge is based on introspective acquaintance with representative images, such as Humean impressions and ideas or twentieth -century sense data, which are supposed to instantiate the qualities of the objects of knowledge. What's fascinating about Reid's argument is that it provides us with a decisive argument of quite a different sort2 against phenomenalism : Lots of external objects are hard, perceptibly so; among their perceptible qualia are their hardnesses. But nowhere within the realm of sense data is there a hardness to be discovered—hence, none that resembles the hardness of my desk in being a hardness.3 Quite simply, the suggestion that we might come to know hardness by acquaintance with images that are themselves hard is one that Wolterstorff finds "preposterous" and "wacky."4 Neither the experience [that I have when I touch a hard body] as a whole nor any ingredient therein has the property of being hard. Lome Falkenstein is Professor of Philosophy, Talbot College, The University of Western Ontario, London, Ontario, Canada N6A 3K7. e-mail: lfalkens@uwo.ca 28 Lome Falkenstein There is no such quality as the sensory experience's hardness—none such as the sense datum's hardness. There couldn't be. Sense data, if there are such entities, aren't the sort of things that could be hard. There couldn't possibly be a quality present in the sense datum [that] resembles the hardness of the object in that both are hardnesses.5 The absurdity Wolterstorff finds in this tenet is so blatant, and the refutation the case of hardness supplies is so "easy" and "briskly decisive" that he wonders how phenomenalist theories of perception could have "held so powerful a grip for so long on the imagination of so many intelligent philosophers ."6 He suggests that the major reason for their mistake may have to do with "the habit of philosophers of concentrating on vision when developing theories of perception and offhandedly assuming that the other senses work pretty much the same way."7 Visual after-images do have qualities of shape and color, and this lends plausibility to the view that we perceive by means of acquaintance with images that instantiate the qualities of the objects they represent. But visual images are certainly not hard, Wolterstorff claims, and once we realize that no images are hard, we are forced to accept that "the model [of perception by means of acquaintance with reflective images ] is of no use for developing a general theory of perception."8 The danger with Wolterstorff's appeal to the case of hardness is that it invites reply by appeal to other cases that pose as serious a problem for Reid as hardness purportedly poses for Hume. I have argued elsewhere that color is such a case.9 However, I propose to offer a different reply here. Rather than charge that Reid's account of visual perception runs into problems that match those encountered by Hume's account of tangible perception, I want to show that Hume's account of tangible perception does not encounter the problems Reid and Wolterstorff think that it does. This is not to say that there are no problems with Hume's account of perception. But it is worth establishing that this particular problem has no currency, not just because accuracy demands that Hume's views be absolved of erroneous objections, but because exposing the error of one objection might lead us to rethink the force of others as well. Wolterstorff's Hume Wolterstorff does not set out to provide an exact or uncontroversial analysis of Hume's thought. His purpose is rather to present what he describes as "a rational reconstruction of a line of thought that gripped [Reid's] predecessors"; it is, moreover...