Direct realism (naïve realism) + issues

• Direct realism (naive realism)

  There are two elements in perception: the perceiver and object perceived. We immediately perceive physical objects without any third thing mediating between the perceiver and the physical object.
• Physical objects are mind-independent
• When we perceive the world, we are directly aware of the objects themselves (no sense data)
• Our senses detect properties of these objects (colours, shapes, etc.) which exist in the world
• Objects retain their properties when unperceived
• When a tree falls over in a forest when there's no one there to hear it, it still makes a sound
• Direct realism


  • It is in tune with common sense
  • It avoids scepticism
  • It has explanatory power - explains how we have knowledge of the world and why we perceive what we do
  • It explains why we agree about what we perceive and is in tune with our sense that we occupy the same universe as everyone else
• When looking at a straight straw half-immersed in a glass of water from a certain angle, it will appear broken or bent
• In such cases, the perceiver is directly aware of the bent-looking straw, but the real straw is not itself broken or bent
• This forces us to distinguish appearances from reality, and conclude that the immediate objects of perception cannot be material objects
• Indirect realists then claim that the immediate objects of perception are sense data, and we come to know about physical objects through our awareness of these sense data
• Bertrand Russell's table example - the table appears white when the light is reflected off it, and brown otherwise, so the table cannot be said to have a particular colour
• The apparent shape of the table also varies depending on the angle from which it is observed
• Russell concludes that "The real table... is not immediately known to us at all, but must be an inference from what is immediately known"
• Berkeley's bowl of water example - if you place one hot hand and one cold hand into a bowl of lukewarm water, the water will appear cold to one and hot to the other
• Berkeley uses this and similar observations to argue that the perceived qualities of objects do not exist in the objects as they are perceived
• lace one hot hand and one cold hand into a bowl of lukewarm water the water will appear cold to one and hot to the other
• Berkeley uses this and similar observations

  To reduce to absurdity the realist claim that the perceived qualities exist in mere as they are perceived
• Berkeley's argument


  1. P1 Direct realism claims material object possess mind-independent properties (such as heat/cold, tasmes, smelh and coloured which we directly perceive

  2. P2 But material objects are perceived to have incompatible properties (for example, cold and hot at the same time)

  3. P3 They cannot possess incompatible properties in reality (this is contradictory)

  4. C Therefore direct realism is false material objects do not possess such properties
• Berkeley's conclusion is rather stronger than Russell's. Russell doesn't deny that objects have real properties, only that we don't perceive them directly as they are. Berkeley's conclusion is that the perceived qualities of objects are in the mind, rather than in the objects
• The perceptual variation argument


  Attacks the assumption of direct realism that we perceive the properties of objects as they really are
• The direct realist can accept that objects may appear differently to perceivers and yet insist that they are nonetheless directly perceived
• Examples of perceptual variation


  • Water which is lukewarm can appear cold to a perceiver
  • A table can appear white or beige, while being brown
  • A table can appear trapezoid when it is rectangular
• We have agreed methods for determining the correct temperature of the water and the true colour of the table. We rarely find ourselves facing genuine disagreement in such cases
• We can explain why the colour appears as it does from different angles in terms of the way light reflects from its surface. We can also explain why the water feels warm or cool - because of the temperatures of our hands relative to that of the water
• Similar explanations for other examples of perceptual variation can be developed using direct realist assumptions. Tastes and smells can appear differently because of differences in the state of the organs of sense
• There is no need to posit the existence of some third thing, the appearance, mediating between the perceiver and perceived
• Argument from hallucination


  1. P1 Hallocinations occur when a person perceives something which doesn't exist outside the mind

  2. C1 So what they perceive, the hallucination, exists only in their mind

  3. P2 Hallucinations can be subjectively indistinguishable from veridical perceptions

  4. P3 But if hallucinations and veridical perceptions are subjectively indistinguishable, then the person imast be aware of the same thing in both cases

  5. C2 So, from C1, P2 and P3, what they are directly aware of during veridical perception must also be in the mind

  6. C3 Hence we perceive the world indirectly and direct realism is fabe
• The fact that hallacinations can be subjectively indistinguishable from veridical perceptions (as in P3) doesn't show that they are the same phenomenon in reality
• The direct realist may argue that hallucinations in fact have a very different causal history from veridical perceptions. Rather than being caused by a physical object impacting on the sense organs, hallucinations are produced by some sort of malfunction in the brain
• Since hallucinations and veridical perceptions are not identical phenomena, even if they are indistinguishable to the person subject to them, it does not follow from the fact that hallucinations occur in the mind that veridical perceptions involve a purely mental element
• Time-lag argument


  1. P1 The light from distant objects (such as the Sun) takes time to reach our eyes

  2. C1 So what we are seeing now may no longer exist

  3. C2 So what we are seeing and what is there are different

  4. P2 This is no less true for physical objects at any distance

  5. C3 And so, what we directly see are appearances not physical objects, and direct realism is false
• The time-lag means that what we are seeing is in the past and so it may have ceased to exist by the time we perceive it. But there is nothing in the direct realist view that commits it to the claim that the moment at which we perceive an object must be simultaneous with the object perceived
• The time-lag doesn't mean that we are seeing objects indirectly, it just means we are seeing them as they were
• There are physiological processes that must take place in our bodies and brains before we can become aware of objects around us, and all these processes take time. But such processes of mediation are not sense data and none of this implies that we are directly aware of sense data or that we must use sense data to infer the existence of objects
• Instead we can say that once we become aware of an object we are aware of the object itself