What do we perceive? Direct realism: we perceive physical objects –When we perceive, we have experiences, but experiences aren ’ t ‘ things ’ and aren ’ t what we perceive Representative (or indirect) realism: when we perceive a physical object, we perceive it ‘ indirectly ’, ‘ via ’ the way it appears to us. –What we perceive ‘ directly ’ is an appearance, an idea immediately present to the mind.
Hume’s objection What we perceive is not the same as what is ‘out there’. Hold your thumb against the moon - which looks bigger? Which is bigger? Look at a red rose under sodium lighting - it looks grey, but it hasn’t changed From the side, look at a straight stick half-submerged in water - it looks bent
Distance and size Does your thumb look bigger than the moon? Or does the moon look further away? How big something looks depends on how far away it looks. Not every aspect of one’s experience is dependent on the physical object alone - apparent size depends on relative distance. We are still directly perceiving thumb and moon - but as well as their size, we perceive their distance.
Primary and secondary qualities Primary qualities: properties of an object that are not related by definition to perceivers, e.g. size, mass, and shape Secondary qualities: properties that are related to perceivers, e.g. colour and smell Do secondary qualities exist ‘ in the mind ’ ? No: they are properties of the object that produce a particular appearance –The rose is red, even under sodium lighting: To be red is to look red to normal perceivers in normal conditions.
Illusion What do we see in cases of illusion? First answer: we see an appearance; but in veridical perception, we see the object itself. Second answer: we see the object, but ‘ as it appears ’ –The properties of how it is and how it appears are both possessed by the object
Hallucination What do we see in hallucinations? There is no object! –Good question!! –But direct realism can still say that hallucination should not be a model for veridical perception.