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 5/7/2019 TSC 2001

Can we have a science of consciousness? 5/7/2019 TSC 2001

Can we have a science of consciousness? 5/7/2019 TSC 2001

Can we have a science of consciousness? Ö Can we have a science of consciousness? 5/7/2019 TSC 2001

More specifically: Can we have a physicalist science of consciousness? 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Overview Look at three influential arguments against the possibility of a physicalist account of consciousness: 5/7/2019 TSC 2001

Overview Look at three influential arguments against the possibility of a physicalist account of consciousness: Nagel: incompatibility of subjective and objective 5/7/2019 TSC 2001

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) 5/7/2019 TSC 2001

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) 5/7/2019 TSC 2001

Overview Show that these arguments only work on a particular and implausible view of science: 5/7/2019 TSC 2001

Overview Show that these arguments only work on a particular and implausible view of science: Objectivity as “the view from nowhere” 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Strategy/Caveats Will argue for the possibility of physicalist accounts of consciousness: 5/7/2019 TSC 2001

Strategy/Caveats Will argue for the possibility of physicalist accounts of consciousness: By refuting three influential arguments against same 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Defining terms “Physicalist” 5/7/2019 TSC 2001

Defining terms “Physicalist” Non-dualistic, ontologically conservative 5/7/2019 TSC 2001

Defining terms “Physicalist” Non-dualistic, ontologically conservative Roughly: business as usual 5/7/2019 TSC 2001

Defining terms “Physicalist” “Account” Non-dualistic, ontologically conservative Roughly: business as usual “Account” 5/7/2019 TSC 2001

Defining terms “Physicalist” “Account” Non-dualistic, ontologically conservative Roughly: business as usual “Account” Scientific 5/7/2019 TSC 2001

Defining terms “Physicalist” “Account” Non-dualistic, ontologically conservative Roughly: business as usual “Account” Scientific Where the action is 5/7/2019 TSC 2001

Defining terms “Physicalist” “Account” “Consciousness” Non-dualistic, ontologically conservative Roughly: business as usual “Account” Scientific Where the action is “Consciousness” 5/7/2019 TSC 2001

Defining terms “Physicalist” “Account” “Consciousness” Non-dualistic, ontologically conservative Roughly: business as usual “Account” Scientific Where the action is “Consciousness” Phenomenal awareness: “hard problem” 5/7/2019 TSC 2001

Nagel’s argument: Subjectivity vs objectivity Consciousness is a subjective phenomenon 5/7/2019 TSC 2001

Nagel’s argument: Subjectivity vs objectivity Consciousness is a subjective phenomenon That is, consciousness is accessible only from a subjective point of view 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Rejecting “The view from nowhere” Nagel’s mistake concerns the nature of objectivity 5/7/2019 TSC 2001

Rejecting “The view from nowhere” Nagel’s mistake concerns the nature of objectivity Not a God’s eye view, not a “perspectiveless perspective” 5/7/2019 TSC 2001

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) 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Jackson’s knowledge argument Suppose there is a scientist, Mary, who has all the physical information about vision, but has never actually seen colour. 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

What to do about Mary? Mary may have all the “physical information”, but does not know everything that science knows about vision 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Chalmers’ argument: the possibility of Zombie Earth Scientific explanations must show how the lower-level facts logically entail what is to be explained 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Rejecting the deductive view of science Showing how low-level facts entail what is to be explained is only one mode of explanation 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Analysis The three arguments rely on an inaccurate view of science: 5/7/2019 TSC 2001

Analysis The three arguments rely on an inaccurate view of science: Perspectiveless 5/7/2019 TSC 2001

Analysis The three arguments rely on an inaccurate view of science: Perspectiveless Exhausted by linguistic information 5/7/2019 TSC 2001

Analysis The three arguments rely on an inaccurate view of science: Perspectiveless Exhausted by linguistic information Explains via logical deduction 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Individualism vs social science Critics of scientific accounts of consciousness unanimously assume the case of the individual 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

Afterword I have only argued that it is possible for physicalist science to provide accounts of consciousness that elude the three objections 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001

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 5/7/2019 TSC 2001