1. In Defense of Physicalist Accounts of Consciousness
Ron Chrisley
School of Cognitive & Computing Sciences, University of Sussex
After October 1st:
School of Computer Science, University of Birmingham
Toward A Science of Consciousness 2001
Skövde, Sweden
August 11, 2001
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2. Can we have a science of consciousness?
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3. Can we have a science of consciousness?
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4. Can we have a science of consciousness?Ö
Can we have a science of consciousness?
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5. More specifically: Can we have a physicalist science of consciousness?
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6. Take-Home Message
If we gain a better understanding of what science is, then we will have a better idea of whether particular scientific accounts of consciousness are possible
I’ll show this by looking at particular case – even if you disagree with the details, you can still agree with the general point
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7. Overview
Look at three influential arguments against the possibility of a physicalist account of consciousness:
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8. Overview
Look at three influential arguments against the possibility of a physicalist account of consciousness:
Nagel: incompatibility of subjective and objective
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9. Overview
Look at three influential arguments against the possibility of a physicalist account of consciousness:
Nagel: incompatibility of subjective and objective
Jackson: knowledge argument (feat. Mary)
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10. Overview
Look at three influential arguments against the possibility of a physicalist account of consciousness:
Nagel: incompatibility of subjective and objective
Jackson: knowledge argument (feat. Mary)
Chalmers: lack of logical supervenience (zombie earth)
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11. Overview
Show that these arguments only work on a particular and implausible view of science:
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12. Overview
Show that these arguments only work on a particular and implausible view of science:
Objectivity as “the view from nowhere”
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13. Overview
Show that these arguments only work on a particular and implausible view of science:
Objectivity as “the view from nowhere”
Science as non-experiential
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14. Overview
Show that these arguments only work on a particular and implausible view of science:
Objectivity as “the view from nowhere”
Science as non-experiential
Explanations as logical deductions
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15. Strategy/Caveats
Will argue for the possibility of physicalist accounts of consciousness:
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16. Strategy/Caveats
Will argue for the possibility of physicalist accounts of consciousness:
By refuting three influential arguments against same
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17. Strategy/Caveats
Will argue for the possibility of physicalist accounts of consciousness:
By refuting three influential arguments against same
Not a direct argument; failure of the three arguments is compatible with the impossibility of physicalist accounts
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18. Strategy/Caveats
Will argue for the possibility of physicalist accounts of consciousness:
By refuting three influential arguments against same
Not a direct argument; failure of the three arguments is compatible with the impossibility of physicalist accounts
Will be brisk, leaving out detail, and assuming familiarity with the three arguments to be rejected
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19. Defining terms
“Physicalist”
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20. Defining terms “Physicalist” Non-dualistic, ontologically conservative
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21. Defining terms “Physicalist” Non-dualistic, ontologically conservative
Roughly: business as usual
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22. Defining terms “Physicalist” “Account”
Non-dualistic, ontologically conservative
Roughly: business as usual
“Account”
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23. Defining terms “Physicalist” “Account”
Non-dualistic, ontologically conservative
Roughly: business as usual
“Account”
Scientific
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24. Defining terms “Physicalist” “Account”
Non-dualistic, ontologically conservative
Roughly: business as usual
“Account”
Scientific
Where the action is
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25. Defining terms “Physicalist” “Account” “Consciousness”
Non-dualistic, ontologically conservative
Roughly: business as usual
“Account”
Scientific
Where the action is
“Consciousness”
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26. Defining terms “Physicalist” “Account” “Consciousness”
Non-dualistic, ontologically conservative
Roughly: business as usual
“Account”
Scientific
Where the action is
“Consciousness”
Phenomenal awareness: “hard problem”
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27. Nagel’s argument: Subjectivity vs objectivity
Consciousness is a subjective phenomenon
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28. Nagel’s argument: Subjectivity vs objectivity
Consciousness is a subjective phenomenon
That is, consciousness is accessible only from a subjective point of view
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29. Nagel’s argument: Subjectivity vs objectivity
Consciousness is a subjective phenomenon
That is, consciousness is accessible only from a subjective point of view
But scientific accounts should be objective
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30. Nagel’s argument: Subjectivity vs objectivity
Consciousness is a subjective phenomenon
That is, consciousness is accessible only from a subjective point of view
But scientific accounts should be objective
Objective accounts are from “no point of view”, or a “God’s-eye view”: contain no subjectivity
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31. Nagel’s argument: Subjectivity vs objectivity
Consciousness is a subjective phenomenon
That is, consciousness is accessible only from a subjective point of view
But scientific accounts should be objective
Objective accounts are from “no point of view”, or a “God’s-eye view”: contain no subjectivity
Thus, science cannot explain subjective consciousness
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32. Rejecting “The view from nowhere”
Nagel’s mistake concerns the nature of objectivity
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33. Rejecting “The view from nowhere”
Nagel’s mistake concerns the nature of objectivity
Not a God’s eye view, not a “perspectiveless perspective”
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34. Rejecting “The view from nowhere”
Nagel’s mistake concerns the nature of objectivity
Not a God’s eye view, not a “perspectiveless perspective”
Rather, a way of negotiating human, perspective-bound views; “a view from anywhere” (Brian Cantwell Smith, On the Origin of Objects)
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35. Rejecting “The view from nowhere”
Nagel’s mistake concerns the nature of objectivity
Not a God’s eye view, not a “perspectiveless perspective”
Rather, a way of negotiating human, perspective-bound views; “a view from anywhere” (Brian Cantwell Smith, On the Origin of Objects)
Thus, no incompatibility between objectivity and subjective experience
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36. Jackson’s knowledge argument
Suppose there is a scientist, Mary, who has all the physical information about vision, but has never actually seen colour.
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37. Jackson’s knowledge argument
Suppose there is a scientist, Mary, who has all the physical information about vision, but has never actually seen colour.
When she eventually does see, say, red, she learns something she didn’t know before: what it’s like to see red
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38. Jackson’s knowledge argument
Suppose there is a scientist, Mary, who has all the physical information about vision, but has never actually seen colour.
When she eventually does see, say, red, she learns something she didn’t know before: what it’s like to see red
So physical information is not all the information about consciousness
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39. Rejecting the non-experiential view of science
Jackson’s mistake is to assume that science is a set of propositions that can be written down and read, independently of experience
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40. Rejecting the non-experiential view of science
Jackson’s mistake is to assume that science is a set of propositions that can be written down and read, independently of experience
Rather, science is an experiential activity, not just the “output” of that activity
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41. Rejecting the non-experiential view of science
Jackson’s mistake is to assume that science is a set of propositions that can be written down and read, independently of experience
Rather, science is an experiential activity, not just the “output” of that activity
To be sure, text plays a big role in the activity of science, but so also does experience
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42. Rejecting the non-experiential view of science
Jackson’s mistake is to assume that science is a set of propositions that can be written down and read, independently of experience
Rather, science is an experiential activity, not just the “output” of that activity
To be sure, text plays a big role in the activity of science, but so also does experience
Science does not aspire to provide an account of anything to anyone independently of their experience
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43. What to do about Mary?
Mary may have all the “physical information”, but does not know everything that science knows about vision
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44. What to do about Mary?
Mary may have all the “physical information”, but does not know everything that science knows about vision
Thus, the fact that she learns something does not indicate some limitation of science
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45. What to do about Mary?
Mary may have all the “physical information”, but does not know everything that science knows about vision
Thus, the fact that she learns something does not indicate some limitation of science
Science presupposes that one already knows what is trying to be explained
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46. What to do about Mary?
Mary may have all the “physical information”, but does not know everything that science knows about vision
Thus, the fact that she learns something does not indicate some limitation of science
Science presupposes that one already knows what is trying to be explained
It does not atempt to make this intelligible for those for whom the problem does not arise
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47. Chalmers’ argument: the possibility of Zombie Earth
Scientific explanations must show how the lower-level facts logically entail what is to be explained
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48. Chalmers’ argument: the possibility of Zombie Earth
Scientific explanations must show how the lower-level facts logically entail what is to be explained
We can imagine a Zombie Earth, physically identical to Earth, but with no consciousness at all
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49. Chalmers’ argument: the possibility of Zombie Earth
Scientific explanations must show how the lower-level facts logically entail what is to be explained
We can imagine a Zombie Earth, physically identical to Earth, but with no consciousness at all
So consciousness is not logically entailed by physical facts
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50. Chalmers’ argument: the possibility of Zombie Earth
Scientific explanations must show how the lower-level facts logically entail what is to be explained
We can imagine a Zombie Earth, physically identical to Earth, but with no consciousness at all
So consciousness is not logically entailed by physical facts
So there cannot be a physicalist explanation of consciousness
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51. Rejecting the deductive view of science
Showing how low-level facts entail what is to be explained is only one mode of explanation
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52. Rejecting the deductive view of science
Showing how low-level facts entail what is to be explained is only one mode of explanation
An explanation need only make it intelligible how something with one description also has another description
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53. Rejecting the deductive view of science
Showing how low-level facts entail what is to be explained is only one mode of explanation
An explanation need only make it intelligible how something with one description also has another description
Scientific understanding consists in a practical capacity to interrelate the two descriptions
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54. Rejecting the deductive view of science
Showing how low-level facts entail what is to be explained is only one mode of explanation
An explanation need only make it intelligible how something with one description also has another description
Scientific understanding consists in a practical capacity to interrelate the two descriptions
Furthermore, our views on what is logically entailed by physics can change: history of science
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55. Analysis The three arguments rely on an inaccurate view of science:
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56. Analysis The three arguments rely on an inaccurate view of science:
Perspectiveless
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57. Analysis The three arguments rely on an inaccurate view of science:
Perspectiveless
Exhausted by linguistic information
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58. Analysis The three arguments rely on an inaccurate view of science:
Perspectiveless
Exhausted by linguistic information
Explains via logical deduction
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59. Analysis The three arguments rely on an inaccurate view of science:
Perspectiveless
Exhausted by linguistic information
Explains via logical deduction
None of these are assumed by a view of science which sees it as a situated, embodied activity carried out by experiencing agents
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60. Analysis The three arguments rely on an inaccurate view of science:
Perspectiveless
Exhausted by linguistic information
Explains via logical deduction
None of these are assumed by a view of science which sees it as a situated, embodied activity carried out by experiencing agents
Content should inform method: Cognitive Science is realising that cognition (even science) is such an activity
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61. Individualism vs social science
Critics of scientific accounts of consciousness unanimously assume the case of the individual
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62. Individualism vs social science
Critics of scientific accounts of consciousness unanimously assume the case of the individual
If an individual cannot achieve X, then science cannot achieve X
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63. Individualism vs social science
Critics of scientific accounts of consciousness unanimously assume the case of the individual
If an individual cannot achieve X, then science cannot achieve X
But there is the possibility that the scientific community as a whole might understand (all aspects of) consciousness, even if no one person does
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64. Afterword
I have only argued that it is possible for physicalist science to provide accounts of consciousness that elude the three objections
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65. Afterword
I have only argued that it is possible for physicalist science to provide accounts of consciousness that elude the three objections
This will be of no use if scientific accounts conform to the (limited) models of science that Nagel, Jackson & Chalmers presuppose
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66. Afterword
I have only argued that it is possible for physicalist science to provide accounts of consciousness that elude the three objections
This will be of no use if scientific accounts conform to the (limited) models of science that Nagel, Jackson & Chalmers presuppose
Scientists should be aware of the wider possibilities when going about their business
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