... David M Armstrong, ‘Perception, Sense Data and Causality’, in G F Macdonald (ed.), Perception and Identity (London: Macmillan, 1979) Sensation and appearance 113 worthiness of our perceptual ... connection between redness and squareness on the one hand and blueness and roundness on the other – that is, it fails to distinguish between the original sense-datum report and the quite different ... Locke’s views about this distinction and more generally about perception, see my Locke on Human Understanding (London: Routledge, 1995), ch Sensation and appearance 121 shape of an object even...