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SENSE PERCEPTION

EQ: What limitations might there be to sense perception as a way of knowing?

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SENSE PERCEPTION AS REALITY?

  • Common sense (direct) realism: the belief that the world is more or less as we perceive it to be with our senses
    • Perception is passive, straightforward
    • Colors, sounds, smells, etc. exist ‘out there’ in the world
    • The act of observation does not affect the nature of what is observed

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Discuss: pros and cons to this theory

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ARTHUR EDDINGTON, BRITISH ASTROPHYSICIST:

“As a conscious being, I am involved in a story. The perceiving part of my mind tells me a story of a world around me... It tells of colors, sound, scents belonging to these objects…

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As a scientist, I have become mistrustful of this story. In many instances it has become clear that things are not what they seem to be. According to the storyteller, I am sitting at a substantial desk; but I have learned from physics that the desk is not at all the continuous substance that it is supposed to be in the story. It is a host of tiny electric charges darting hither and thither with inconceivable velocity. Instead of being solid substance, my desk is more like a swarm of gnats.

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So I have come to realize that I must not put overmuch confidence in the storyteller who lives in my mind.”

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SENSE PERCEPTION AS REALITY?

SO: Perhaps common-sense realism doesn’t hold up

Sense perception (like all knowledge) provides us with a MODEL of the world, not the world itself.

  • Indirect realism (representationalism):

We do not & cannot perceive the external world as it actually is: we only know our ideas/interpretations of the way the world is]

  • Video

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CAN OUR SENSE PERCEPTION BE INACCURATE?

Describe these tables using the evidence of your eyes (sense perception):

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  • The parallelograms are exactly the same size
  • Illusion created by Robert M. Shepard, a Stanford psychologist
  • Your brain and eyes decode them according to the rules for three-dimensional objects because of the legs

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CAN OUR SENSE PERCEPTION BE INACCURATE? CONT.

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IS OUR SENSE PERCEPTION COMPREHENSIVE?

    • Selective Attention: the process of directing our awareness to relevant stimuli/ ignoring irrelevant
    • KQ: How do our expectations & assumptions have an impact on how we perceive things?
    • Texting & driving?
    • Eyewitness testimony?
  • Thus: Our brains are not capable of processing ALL info available
  • It is estimated that your brain takes in billions of bits of sensory data every second, but it can only process about 2000.

Awareness Test

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PROCESSING SENSORY INPUT

  • How does your brain decide which 2000 bits per second?
  • One possibility: the stage model of memory see diagram
  • Stage one is unconscious
    • Your brain does its best to sort (usually related to what you are doing, or what is expected)
    • When recalling: it has to fill in the gaps (memory like a series of photographs, not a film)

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IS OUR SENSE PERCEPTION UNIVERSAL?

  • How do we know that our sense perception is accurate? The same as others’?
  • Synesthesia:
    • a perceptual phenomenon where stimulation of one sensory/cognitive pathway automatically triggers involuntary experience in a second
    • Examples:
    • Seeing numbers in color
    • Seeing music in color
    • Tasting shapes or colors or words
    • And many more
  • Thus: not all sense perception is the same
  • KQ: Is the truth what the majority of people accept?

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IS OUR SENSE PERCEPTION LIMITED?

  • Sharks
  • Birds
  • Ants
  • Sargasso eels
  • Mantis shrimp
  • Bats

The range of what humans can see and hear represents only a tiny portion of the range of all possible light and sound

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CAN OUR SENSE PERCEPTION BE EXTENDED?

  • Technology has the capability to extend our sense perception
  • KQ: How does technology extend or transform different modes of human cognition and communication?
  • DISCUSS: What ethical issues does technology raise?
  • KQ: How should these be decided?

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SO, CONCLUSIONS ABOUT SENSE PERCEPTION?

We are only capable of perceiving SOME of the reality that actually exists

AND, even given what we can perceive, we cannot accurately process ALL of it

IF we assume there is a “reality” that exists outside our minds . . .

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THOUGHT EXPERIMENT:�WHAT IS REALLY OUT THERE?

  • Where is the pain?
    • In the water? In the hand? In the mind?
  • Sensory input is converted to electrical impulses, which the brain decodes as ‘pain’
  • So, there is no ‘pain’ in the world of things—the water appears painful TO ME but is not objectively painful
  • Where is the color?
  • DISCUSS: So what exists ‘out there’ in the world, vs. just in our minds?
  • Does it matter?