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Geoffrey Lee

University of California, Berkeley, Philosophy, Faculty Member

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Phone: 646 361 3802
Address: Department of Philosophy
314 Moses Hall #2390
University of California
Berkeley, CA 94720-2390

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Papers by Geoffrey Lee

Against Magnitude Realism

Crítica (México D. F. En línea)

In recent work, Christopher Peacocke has argued for a kind of realism (or anti-reductionism) abou... more In recent work, Christopher Peacocke has argued for a kind of realism (or anti-reductionism) about magnitudes such as temperature and spatial distance. Peacocke’s argument is that magnitudes are an ineliminable commitment of scientific and everyday explanations (including high-level explanations), and that they are the natural candidates for semantic values of our ordinary magnitude talk, and for contents of our mental states. I critique these arguments, in particular focusing on whether the realist has a satisfactory account of how high-level magnitude facts are grounded in lower-level facts. I argue that a less realist (i.e., more reductionist approach) is preferable, or at least viable. I also aim to substantially clarify what is at stake in the debate.

Idealism and the Interface Theory

This paper argues that there is a non-standard but theoretically important notion of “veridicalit... more This paper argues that there is a non-standard but theoretically important notion of “veridicality”, on which perception is only veridical if it does not scramble the objective physical structure of the environment. I argue that non-veridicality in this sense is compatible with veridicality in more familiar senses, and motivate the importance of the notion. For example, I think a certain kind of realism about the scientific enterprise (that it can uncover nature’s natural structure by inference from the manifest image), assumes that perception is veridical in this sense. I think the best reconstruction of Hoffman, Singh and Prakah’s “Interface Theory” is as the view that perception is non-veridical in this non-standard sense – a view that I think is reasonably understood as a kind of transcendental idealism, because it makes the objective structure of the world unknowable to us. They offer debunking arguments against perceptual veridicality (in this special sense). I respond to these arguments, and sketch a realist alternative.

Against Magnitude Realism

Ordinary experience, thought and talk predicates families of properties to objects that are commo... more Ordinary experience, thought and talk predicates families of properties to objects that are commonly known as magnitudes or quantities. Familiar examples include spatial distance, duration, weight, volume, and temperature. My topic here is a kind of realism (or anti-reductionism) about these magnitudes that has been argued for in recent work by Christopher Peacocke (2014, 2019 ch.2). In brief, Peacocke's argument for realism about these magnitudes is that they are an ineliminable commitment of scientific and everyday explanation (including high-level explanations), that they are the natural candidates for semantic values of our ordinary magnitude talk (which is hard to give a plausible semantics for without them) and also that they are well-suited to serve a role in constituting the contents of our perceptual experiences and perceptual states (for example, perceptions of spatial distances). I will critique his arguments and suggest that, for all he has said, a less realist (i.e. more reductionist) approach to magnitudes is preferable, or at least viable. I also aim to substantially clarify what is at stake in the debate.

Representing Probability in Perception and Experience

by Geoffrey Lee and Nico Orlandi

Review of Philosophy and Psychology

It is increasingly common in cognitive science and philosophy of perception to regard perceptual ... more It is increasingly common in cognitive science and philosophy of perception to regard perceptual processing as a probabilistic engine, taking into account uncertainty in computing representations of the distal environment. Models of this kind often postulate probabilistic representations, or what we will call probabilistic states,. These are states that in some sense mark or represent information about the probabilities of distal conditions. It has also been argued that perceptual experience itself in some sense represents uncertainty (Morrison Analytic Philosophy 57 (1): 15 48, 2016). In this article, we will first consider three models of sensory activity from perceptual neuroscience, namely signal detection theory (SDT), probabilistic population codes (PPC), and sampling. We will then reflect on the sense in which the probabilistic states introduced in these models are probabilistic representations. To sharpen this discussion, we will compare and contrast these probabilistic states to credences as they are understood in epistemology. We will suggest that probabilistic representation, in an appropriately robust sense, can be understood as a form of analog representation. In the last part of the paper, we apply this to the issue of whether conscious experience represents uncertainty-we will interpret this as the claim that there are phenomenal features of experience that serve as analog probabilistic representations.

Representing Probability in Perception and Experience

Review of Philosophy of Psychology, 2022

It is increasingly common in cognitive science and philosophy of perception to regard perceptual ... more It is increasingly common in cognitive science and philosophy of perception to regard perceptual processing as a probabilistic engine, taking into account uncertainty in computing representations of the distal environment. Models of this kind often postulate probabilistic representations, or what we will call probabilistic states,. These are states that in some sense mark or represent information about the probabilities of distal conditions. It has also been argued that perceptual experience itself in some sense represents uncertainty (Morrison Analytic Philosophy 57 (1): 15 48, 2016). In this article, we will first consider three models of sensory activity from perceptual neuroscience, namely signal detection theory (SDT), probabilistic population codes (PPC), and sampling. We will then reflect on the sense in which the probabilistic states introduced in these models are probabilistic representations. To sharpen this discussion, we will compare and contrast these probabilistic states to credences as they are understood in epistemology. We will suggest that probabilistic representation, in an appropriately robust sense, can be understood as a form of analog representation. In the last part of the paper, we apply this to the issue of whether conscious experience represents uncertainty-we will interpret this as the claim that there are phenomenal features of experience that serve as analog probabilistic representations.

The Experience of Left and Right

Perceptual Experience, 2006

Smithies, Sebastian Watzl, and two anonymous referees (you know who you are). 1 Or, our knowledge... more Smithies, Sebastian Watzl, and two anonymous referees (you know who you are). 1 Or, our knowledge thereof. Transcendental arguments typically have conclusions like 'there is an external world', or 'I am not a brain in a vat', rather than, e.g., 'I know that there is an external world'. 2 Martin Davies (1992) has attempted to run a similar kind of argument, in his case from armchair considerations to the conclusion that there is a Language of Thought. 3 For a classic discussion, see Shoemaker (1982).

SELFLESS EXPERIENCE

Selfless Experience, 2018

This paper discusses a neo-Humean view on which the experiences within a single stream of conscio... more This paper discusses a neo-Humean view on which the experiences within a single stream of consciousness can be understood without reference to a self, in a certain sense. More specifically, it discusses what I call the 'Subject Non-identity Thesis". If conscious experiences are understood as instantiations of experiential properties, we can define the "logical subject" of an experience as the object instantiating the relevant property. According to the Subject Non-identity thesis, different experiences within a stream of consciousness, even those occurring at the same time, may not have the same logical subject; for example, their logical subjects might be different brain regions. I explain why this is a plausible view, and defend it against a number of objections.

How Radical is Predictive Processing?

by Geoffrey Lee and Nico Orlandi

We discuss Andy Clark's recent explorations of Bayesian perceptual models and predictive processi... more We discuss Andy Clark's recent explorations of Bayesian perceptual models and predictive processing, as laid out in his book "Surfing Uncertainty". In the first part of this chapter, we discuss the predictive processing framework (PP), explicating its relationship with hierarchical Bayesian models in theories of perception. In the second part, we examine the relationship between perception and action in the PP model. Our overarching goal is twofold. We would like, first, to get clearer on the picture of mental activity that Clark is presenting. Second, we point out that, although the framework presented by Clark certainly has interesting novel features, some of Clark's glosses on it are misleading. In particular, we think that Clark's interpretation of predictive processing as essentially a top-down, expectation-driven process, on which perception is aptly thought of as " controlled hallucination " , exaggerates the contrast with the traditional picture of perception as bottom-up and stimulus driven. Additionally, we think that, despite the rhetoric, Clark's PP model substantially preserves the traditional distinction between perception and action.

Explaining away temporal flow - thoughts on Prosser's "Experiencing Time"

Forthcoming in "Inquiry" in a symposium on Prosser's 2016 book "Experiencing Time". Discusses the... more

Making Sense of Subjective Time

In "The Routledge Handbook of the Philosophy of Temporal Experience", edited by Ian Phillips (201... more In "The Routledge Handbook of the Philosophy of Temporal Experience", edited by Ian Phillips (2017). Overview of some of the key philosophical problems in understanding subjective time, with a focus on the experience of duration. See also my unpublished paper "Subjective Duration" (available here), which covers some different issues in the same area.

Does Experience Have Phenomenal Properties?

What assumptions are built into the claim that experience has “phenomenal properties,” and could ... more What assumptions are built into the claim that experience has “phenomenal properties,” and could these assumptions turn out to be false? I consider the issue specifically for the similarity relations between experiences: for example, experiences of different shades of red are more similar to each other than an experience of red and an experience of green. It is commonly thought that we have a special kind of epistemic access to experience that is more secure than our access to the external environment. In the first part of the paper, I argue than one way of eluci- dating this claim is especially plausible—that systematic error, of the kind subjects make about the external environment in traditional “skeptical” scenarios, is not conceivable for introspection of experience, including for our knowledge of similarity relations. I argue that focusing on simi- larity relations gives us a more interesting version of the argument than for other forms of experiential introspection. Then in the second part of the paper I describe an example, inspired by a similar case due to Sydney Shoemaker, in which a subject, despite being fully rational and attentive, apparently is systematically mistaken about the character of their expe- rience in a surprising way. I argue that the example calls into question whether there are properties of experience satisfying the epistemic access constraint, and therefore whether experience has “phenomenal properties” in the intuitive sense.

Review of Jesse Prinz "The Conscious Brain"

Materialism and the Epistemic Significance of Consciousness

This is a companion piece to "Alien Subjectivity and the Importance of Consciousness". It argues ... more This is a companion piece to "Alien Subjectivity and the Importance of Consciousness". It argues that if Reductive Materialism is true, this gives us a reason to doubt that conscious experience is unique in its epistemic features: epistemically, being a zombie could be just just as good as being conscious.

Alien Subjectivity and the Importance of Consciousness

I argue that reductive materialism supports a deflationary view of consciousness I call "Deflati... more I argue that reductive materialism supports a deflationary view of consciousness I call "Deflationary Pluralism". The Deflationary Pluralist believes that a creature that lacked phenomenal consciousness could have "quasi-conscious" states that have a similar functional profile to our conscious states, and which are just as significant as conscious states, in various senses: their quasi-consciousness is just as deep a joint in nature as our consciousness, and is just as epistemically and morally important.

Experiences and their Parts

I give an account of the difference between "Holistic" and "Atomistic" views of conscious experie... more I give an account of the difference between "Holistic" and "Atomistic" views of conscious experience. On the Holistic view, we enjoy a unified "field" of awareness, whose parts are mere modifications of the whole, and therefore owe their existence to the whole. There is some tendency to saddle those who reject the Holistic field model with a (perhaps) implausible "building block" view. I distinguish a number of different theses about the parts of an experience that are suggested by the "building block" metaphor, but which can be rejected by those who also reject the holistic field view.

Unity and Essence in Chalmers' Theory of Consciousness

This paper is part of a symposium on David Chalmers book "The Character of Consciousness".

Subjective Duration

I argue against the idea that the stream of consciousness exists within a dimenson of "phenomenal... more I argue against the idea that the stream of consciousness exists within a dimenson of "phenomenal time" that provides a measure of how long an experience feels subjectively. I argue that this view conflicts with my preferred Atomistic view of temporal experience (defended in "Temporal Experience and the Temporal Structure of Experience"), and that attempts to reduce phenomenal rate of passage to other measure on the stream, such as measure of how much information is flowing through conscious awareness, do not succeed. I hold that temporally extended experiences only have subjective duration in a thin retrospective sense, and that this fact threatens to undermine some deeply held intutions about what we care about in having experiences of different kinds.

Extensionalism, Atomism, and Continuity

This paper defends the Atomic view I argue for in "Temporal Experience and the Temporal Structure... more This paper defends the Atomic view I argue for in "Temporal Experience and the Temporal Structure of Experience" from objections against it that can be found in the literature. I focus in particular on Phillips' objection that Atomism is inconsistent with the correct account of how we are introspectively aware of experience changing over time, and Dainton's objection that Atomism is inconsistent with the felt continuity of experience.

Temporal Experience and the Temporal Structure of Experience

Consciousness in a Space-Time World

Against Magnitude Realism

Crítica (México D. F. En línea)

In recent work, Christopher Peacocke has argued for a kind of realism (or anti-reductionism) abou... more In recent work, Christopher Peacocke has argued for a kind of realism (or anti-reductionism) about magnitudes such as temperature and spatial distance. Peacocke’s argument is that magnitudes are an ineliminable commitment of scientific and everyday explanations (including high-level explanations), and that they are the natural candidates for semantic values of our ordinary magnitude talk, and for contents of our mental states. I critique these arguments, in particular focusing on whether the realist has a satisfactory account of how high-level magnitude facts are grounded in lower-level facts. I argue that a less realist (i.e., more reductionist approach) is preferable, or at least viable. I also aim to substantially clarify what is at stake in the debate.

Idealism and the Interface Theory

This paper argues that there is a non-standard but theoretically important notion of “veridicalit... more This paper argues that there is a non-standard but theoretically important notion of “veridicality”, on which perception is only veridical if it does not scramble the objective physical structure of the environment. I argue that non-veridicality in this sense is compatible with veridicality in more familiar senses, and motivate the importance of the notion. For example, I think a certain kind of realism about the scientific enterprise (that it can uncover nature’s natural structure by inference from the manifest image), assumes that perception is veridical in this sense. I think the best reconstruction of Hoffman, Singh and Prakah’s “Interface Theory” is as the view that perception is non-veridical in this non-standard sense – a view that I think is reasonably understood as a kind of transcendental idealism, because it makes the objective structure of the world unknowable to us. They offer debunking arguments against perceptual veridicality (in this special sense). I respond to these arguments, and sketch a realist alternative.

Against Magnitude Realism

Ordinary experience, thought and talk predicates families of properties to objects that are commo... more Ordinary experience, thought and talk predicates families of properties to objects that are commonly known as magnitudes or quantities. Familiar examples include spatial distance, duration, weight, volume, and temperature. My topic here is a kind of realism (or anti-reductionism) about these magnitudes that has been argued for in recent work by Christopher Peacocke (2014, 2019 ch.2). In brief, Peacocke's argument for realism about these magnitudes is that they are an ineliminable commitment of scientific and everyday explanation (including high-level explanations), that they are the natural candidates for semantic values of our ordinary magnitude talk (which is hard to give a plausible semantics for without them) and also that they are well-suited to serve a role in constituting the contents of our perceptual experiences and perceptual states (for example, perceptions of spatial distances). I will critique his arguments and suggest that, for all he has said, a less realist (i.e. more reductionist) approach to magnitudes is preferable, or at least viable. I also aim to substantially clarify what is at stake in the debate.

Representing Probability in Perception and Experience

by Geoffrey Lee and Nico Orlandi

Review of Philosophy and Psychology

It is increasingly common in cognitive science and philosophy of perception to regard perceptual ... more It is increasingly common in cognitive science and philosophy of perception to regard perceptual processing as a probabilistic engine, taking into account uncertainty in computing representations of the distal environment. Models of this kind often postulate probabilistic representations, or what we will call probabilistic states,. These are states that in some sense mark or represent information about the probabilities of distal conditions. It has also been argued that perceptual experience itself in some sense represents uncertainty (Morrison Analytic Philosophy 57 (1): 15 48, 2016). In this article, we will first consider three models of sensory activity from perceptual neuroscience, namely signal detection theory (SDT), probabilistic population codes (PPC), and sampling. We will then reflect on the sense in which the probabilistic states introduced in these models are probabilistic representations. To sharpen this discussion, we will compare and contrast these probabilistic states to credences as they are understood in epistemology. We will suggest that probabilistic representation, in an appropriately robust sense, can be understood as a form of analog representation. In the last part of the paper, we apply this to the issue of whether conscious experience represents uncertainty-we will interpret this as the claim that there are phenomenal features of experience that serve as analog probabilistic representations.

Representing Probability in Perception and Experience

Review of Philosophy of Psychology, 2022

It is increasingly common in cognitive science and philosophy of perception to regard perceptual ... more It is increasingly common in cognitive science and philosophy of perception to regard perceptual processing as a probabilistic engine, taking into account uncertainty in computing representations of the distal environment. Models of this kind often postulate probabilistic representations, or what we will call probabilistic states,. These are states that in some sense mark or represent information about the probabilities of distal conditions. It has also been argued that perceptual experience itself in some sense represents uncertainty (Morrison Analytic Philosophy 57 (1): 15 48, 2016). In this article, we will first consider three models of sensory activity from perceptual neuroscience, namely signal detection theory (SDT), probabilistic population codes (PPC), and sampling. We will then reflect on the sense in which the probabilistic states introduced in these models are probabilistic representations. To sharpen this discussion, we will compare and contrast these probabilistic states to credences as they are understood in epistemology. We will suggest that probabilistic representation, in an appropriately robust sense, can be understood as a form of analog representation. In the last part of the paper, we apply this to the issue of whether conscious experience represents uncertainty-we will interpret this as the claim that there are phenomenal features of experience that serve as analog probabilistic representations.

The Experience of Left and Right

Perceptual Experience, 2006

Smithies, Sebastian Watzl, and two anonymous referees (you know who you are). 1 Or, our knowledge... more Smithies, Sebastian Watzl, and two anonymous referees (you know who you are). 1 Or, our knowledge thereof. Transcendental arguments typically have conclusions like 'there is an external world', or 'I am not a brain in a vat', rather than, e.g., 'I know that there is an external world'. 2 Martin Davies (1992) has attempted to run a similar kind of argument, in his case from armchair considerations to the conclusion that there is a Language of Thought. 3 For a classic discussion, see Shoemaker (1982).

SELFLESS EXPERIENCE

Selfless Experience, 2018

This paper discusses a neo-Humean view on which the experiences within a single stream of conscio... more This paper discusses a neo-Humean view on which the experiences within a single stream of consciousness can be understood without reference to a self, in a certain sense. More specifically, it discusses what I call the 'Subject Non-identity Thesis". If conscious experiences are understood as instantiations of experiential properties, we can define the "logical subject" of an experience as the object instantiating the relevant property. According to the Subject Non-identity thesis, different experiences within a stream of consciousness, even those occurring at the same time, may not have the same logical subject; for example, their logical subjects might be different brain regions. I explain why this is a plausible view, and defend it against a number of objections.

How Radical is Predictive Processing?

by Geoffrey Lee and Nico Orlandi

We discuss Andy Clark's recent explorations of Bayesian perceptual models and predictive processi... more We discuss Andy Clark's recent explorations of Bayesian perceptual models and predictive processing, as laid out in his book "Surfing Uncertainty". In the first part of this chapter, we discuss the predictive processing framework (PP), explicating its relationship with hierarchical Bayesian models in theories of perception. In the second part, we examine the relationship between perception and action in the PP model. Our overarching goal is twofold. We would like, first, to get clearer on the picture of mental activity that Clark is presenting. Second, we point out that, although the framework presented by Clark certainly has interesting novel features, some of Clark's glosses on it are misleading. In particular, we think that Clark's interpretation of predictive processing as essentially a top-down, expectation-driven process, on which perception is aptly thought of as " controlled hallucination " , exaggerates the contrast with the traditional picture of perception as bottom-up and stimulus driven. Additionally, we think that, despite the rhetoric, Clark's PP model substantially preserves the traditional distinction between perception and action.

Explaining away temporal flow - thoughts on Prosser's "Experiencing Time"

Forthcoming in "Inquiry" in a symposium on Prosser's 2016 book "Experiencing Time". Discusses the... more

Making Sense of Subjective Time

In "The Routledge Handbook of the Philosophy of Temporal Experience", edited by Ian Phillips (201... more In "The Routledge Handbook of the Philosophy of Temporal Experience", edited by Ian Phillips (2017). Overview of some of the key philosophical problems in understanding subjective time, with a focus on the experience of duration. See also my unpublished paper "Subjective Duration" (available here), which covers some different issues in the same area.

Does Experience Have Phenomenal Properties?

What assumptions are built into the claim that experience has “phenomenal properties,” and could ... more What assumptions are built into the claim that experience has “phenomenal properties,” and could these assumptions turn out to be false? I consider the issue specifically for the similarity relations between experiences: for example, experiences of different shades of red are more similar to each other than an experience of red and an experience of green. It is commonly thought that we have a special kind of epistemic access to experience that is more secure than our access to the external environment. In the first part of the paper, I argue than one way of eluci- dating this claim is especially plausible—that systematic error, of the kind subjects make about the external environment in traditional “skeptical” scenarios, is not conceivable for introspection of experience, including for our knowledge of similarity relations. I argue that focusing on simi- larity relations gives us a more interesting version of the argument than for other forms of experiential introspection. Then in the second part of the paper I describe an example, inspired by a similar case due to Sydney Shoemaker, in which a subject, despite being fully rational and attentive, apparently is systematically mistaken about the character of their expe- rience in a surprising way. I argue that the example calls into question whether there are properties of experience satisfying the epistemic access constraint, and therefore whether experience has “phenomenal properties” in the intuitive sense.

Review of Jesse Prinz "The Conscious Brain"

Materialism and the Epistemic Significance of Consciousness

This is a companion piece to "Alien Subjectivity and the Importance of Consciousness". It argues ... more This is a companion piece to "Alien Subjectivity and the Importance of Consciousness". It argues that if Reductive Materialism is true, this gives us a reason to doubt that conscious experience is unique in its epistemic features: epistemically, being a zombie could be just just as good as being conscious.

Alien Subjectivity and the Importance of Consciousness

I argue that reductive materialism supports a deflationary view of consciousness I call "Deflati... more I argue that reductive materialism supports a deflationary view of consciousness I call "Deflationary Pluralism". The Deflationary Pluralist believes that a creature that lacked phenomenal consciousness could have "quasi-conscious" states that have a similar functional profile to our conscious states, and which are just as significant as conscious states, in various senses: their quasi-consciousness is just as deep a joint in nature as our consciousness, and is just as epistemically and morally important.

Experiences and their Parts

I give an account of the difference between "Holistic" and "Atomistic" views of conscious experie... more I give an account of the difference between "Holistic" and "Atomistic" views of conscious experience. On the Holistic view, we enjoy a unified "field" of awareness, whose parts are mere modifications of the whole, and therefore owe their existence to the whole. There is some tendency to saddle those who reject the Holistic field model with a (perhaps) implausible "building block" view. I distinguish a number of different theses about the parts of an experience that are suggested by the "building block" metaphor, but which can be rejected by those who also reject the holistic field view.

Unity and Essence in Chalmers' Theory of Consciousness

This paper is part of a symposium on David Chalmers book "The Character of Consciousness".

Subjective Duration

I argue against the idea that the stream of consciousness exists within a dimenson of "phenomenal... more I argue against the idea that the stream of consciousness exists within a dimenson of "phenomenal time" that provides a measure of how long an experience feels subjectively. I argue that this view conflicts with my preferred Atomistic view of temporal experience (defended in "Temporal Experience and the Temporal Structure of Experience"), and that attempts to reduce phenomenal rate of passage to other measure on the stream, such as measure of how much information is flowing through conscious awareness, do not succeed. I hold that temporally extended experiences only have subjective duration in a thin retrospective sense, and that this fact threatens to undermine some deeply held intutions about what we care about in having experiences of different kinds.

Extensionalism, Atomism, and Continuity

This paper defends the Atomic view I argue for in "Temporal Experience and the Temporal Structure... more This paper defends the Atomic view I argue for in "Temporal Experience and the Temporal Structure of Experience" from objections against it that can be found in the literature. I focus in particular on Phillips' objection that Atomism is inconsistent with the correct account of how we are introspectively aware of experience changing over time, and Dainton's objection that Atomism is inconsistent with the felt continuity of experience.

Temporal Experience and the Temporal Structure of Experience

Consciousness in a Space-Time World

Selfless Experience

This paper discusses a neo-Humean view on which the experiences within a single stream of conscio... more This paper discusses a neo-Humean view on which the experiences within a single stream of consciousness can be understood without reference to a self, in a certain sense. More specifically, it discusses what I call the 'Subject Non-identity Thesis". If conscious experiences are understood as instantiations of experiential properties, we can define the "logical subject" of an experience as the object instantiating the relevant property. According to the Subject Non-identity thesis, different experiences within a stream of consciousness, even those occurring at the same time, may not have the same logical subject; for example, their logical subjects might be different brain regions. I explain why this is a plausible view, and defend it against a number of objections.

Selfless Experience

This paper discusses a neo-Humean view on which the experiences within a single stream of conscio... more This paper discusses a neo-Humean view on which the experiences within a single stream of consciousness can be understood without reference to a self, in a certain sense. More specifically, it discusses what I call the 'Subject Non-identity Thesis". If conscious experiences are understood as instantiations of experiential properties, we can define the "logical subject" of an experience as the object instantiating the relevant property. According to the Subject Non-identity thesis, different experiences within a stream of consciousness, even those occurring at the same time, may not have the same logical subject; for example, their logical subjects might be different brain regions. I explain why this is a plausible view, and defend it against a number of objections.