Amherst I'm looking at the snowy woods behind my house through the window. I see the (still) whit... more Amherst I'm looking at the snowy woods behind my house through the window. I see the (still) white snow on the ground, the grayish/brownish trunks of the trees, and the dark green needles. The sky is bright and blue. I have had my two morning cups of coffee, so I'm as awake as I ever am. I am having a conscious visual experience, and the conditions are as propitious for veridical perception as they can be. Though a skeptic could engender doubts if I let her, I am morally certain that I am indeed consciously seeing snow, trees, and sky. No doubt about it. Let "E" be the conscious visual experience I just described, which I am having as I write these words. It is natural to think of E as a state I'm in, a mental state-an occurrent mental state. Another natural thing to say, though it now has a technical ring to it, is that "there is something it's like for me to occupy state E". The point is, I occupy many states right now, and for most of them there is nothing it is like to occupy them. Some of these states there is nothing it is like for me to occupy are even occurrent mental states. For instance, I occupy the state of having certain visual receptors fire, or of certain language center modules assigning thematic roles to the constituents of the sentences I am now formulating. Unaware of these processes and states as I am, there is nothing it is like for me to occupy them. But when it comes to the conscious visual experience, clearly there is something it's like for me. What it's like for me to have this conscious visual experience it's now common to call its "phenomenal character". We can thus think of phenomenal character as the answer to the question, "what is it like for you to see what you see now?" Now, in general, if someone asks what X is like-whether it be an object, event, or state-the answer, that it is like P, seems to involve predicating a property of X. "What is your dog like? She's very friendly." I'm claiming that
How do we imagine these sensory qualities being instantiated in experiences? Clearly, on Clark’s ... more How do we imagine these sensory qualities being instantiated in experiences? Clearly, on Clark’s account, for a sensory quality to be instantiated in an experience is for the brain to occupy a certain state. The question then becomes how the brain’s states count as realizing the relevant quality space, so that any one state can be mapped onto a location in that space. Well, there are two possibilities. First, if brain states maintained relations of similarity that respected the topology of the color quality space, that would justify mapping individual states onto their respective locations in that space. But of course that isn’t likely, or what I imagine Clark has in mind. There isn’t going to be any well-defined notion of neural similarity that will
The present paper deals with three sources of holistic arguments: confirmation of scientific theo... more The present paper deals with three sources of holistic arguments: confirmation of scientific theories, translation between languages, relationships between belief, meaning and reference. Confirmation holism (CH), belief holism (BH) and meaning holism (MH) are the main theses to be examined. However, the various topics are thought of as instrumental to the clarification of MH, a position whose identification depends on the status assigned to meanings. To fix ideas, MH can be taken as saying that the meaning of any sentence (or term) is given by the totality of its semantic links, thus, in order to talk about its meaning, a wide set of other sentences (terms) is required, yet there is no definite set of such sentences, it's always a jigsaw puzzle of interpretation, where each piece has no autonomous meaning.
Siewert's book revolves around three theses: that there is a distinctive style of epistemic w... more Siewert's book revolves around three theses: that there is a distinctive style of epistemic warrant associated with the first-person point of view, that if we pay close attention to the deliverances of this first-person point of view, we will see that phenomenal consciousness is both real and yet neglected by many current theories that purport to explain consciousness, and that phenomenal consciousness is inherently intentional; one cannot divorce what phenomenal character presents to us from what it's like to have it. Among several points made on the relations among these three theses, it is argued that Siewert's argument for the distinctive status of first-person warrant does not provide him with the support necessary to employ that thesis in his defense of the significance of phenomenal consciousness. Siewert's book aims to establish, as the title announces, the "significance" of consciousness. He does this by arguing in great detail for three principal ...
In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, tha... more In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, that pick out individuals, from type-demonstratives, that pick out kinds, or properties, and provide a similar treatment for both. I argue that it follows from my model of demonstrative thought, as well as from independent considerations, that demonstration, as a mental act, operates directly on mental representations, not external objects. That is, though the relation between a demonstrative and the object or property demonstrated is semantically direct, the mechanism by which a demonstrative acquires its referent involves mediation by a perceptual representation. Finally, I argue that so-called 'demonstrative concepts'-which I treat as type-demonstratives-cannot perform the various philosophical functions that have been assigned to them.
Background-Ventricular tachyarrhythmias long enough to cause implantable cardioverter defibrillat... more Background-Ventricular tachyarrhythmias long enough to cause implantable cardioverter defibrillator (ICD) shocks are generally thought to progress to cardiac arrest. In previous ICD trials, shocks have been considered an appropriate surrogate for sudden cardiac death (SCD) because the number of shocks has been thought to be equivalent to the mortality excess in patients without ICDs. The practice of equating ICD shocks with mortality is controversial and has not been validated critically. Methods and Results-The Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial was a prospective, randomized, multicenter trial of ICD therapy in 458 patients with nonischemic cardiomyopathy. Patients were randomized to receive standard medical therapy (STD) or STD plus an ICD. Shock electrograms were reviewed, and the cause of death was evaluated by a separate blinded events committee. There were 15 SCD or cardiac arrests in the STD group and only 3 in the ICD arm. In contrast, of the 229 patients randomized to an ICD, 33 received 70 appropriate ICD shocks. Patients in the ICD arm were more likely to have an arrhythmic event (ICD shock plus SCD) than patients in the STD arm (hazard ratio 2.12, 95% CI 1.153 to 3.893, Pϭ0.013). The number of arrhythmic events when one includes syncope as a potential arrhythmic event was similar in both groups (hazard ratio 1.20, 95% CI 0.774 to 1.865, Pϭ0.414). Approximately the same number of total events was noted in each arm when we compared syncope plus SCD/cardiac arrest in the STD arm with SCD plus ICD shocks plus syncope in the ICD arm. Conclusions-Appropriate ICD shocks occur more frequently than SCD in patients with nonischemic cardiomyopathy. This suggests that episodes of nonsustained ventricular tachycardia frequently terminate spontaneously in such patients.
Covalent modification cycles (e.g., phosphorylation-dephosphorylation) underlie most cellular sig... more Covalent modification cycles (e.g., phosphorylation-dephosphorylation) underlie most cellular signaling and control processes. Low molecular copy number, arising from compartmental segregation and slow diffusion between compartments, potentially renders these cycles vulnerable to intrinsic chemical fluctuations. How can a cell operate reliably in the presence of this inherent stochasticity? How do changes in extrinsic parameters lead to variability of response? Can cells exploit these parameters to tune cycles to different ranges of stimuli? We study the dynamics of an isolated phosphorylation cycle. Our model shows that the cycle transmits information reliably if it is tuned to an optimal parameter range, despite intrinsic fluctuations and even for small input signal amplitudes. At the same time, the cycle is sensitive to changes in the concentration and activity of kinases and phosphatases. This sensitivity can lead to significant cell-to-cell response variability. It also provides a mechanism to tune the cycle to transmit signals in various amplitude ranges. Our results show that signaling cycles possess a surprising combination of robustness and tunability. This combination makes them ubiquitous in eukaryotic signaling, optimizing signaling in the presence of fluctuations using their inherent flexibility. On the other hand, cycles tuned to suppress intrinsic fluctuations can be vulnerable to changes in the number and activity of kinases and phosphatases. Such trade-offs in robustness to intrinsic and extrinsic fluctuations can influence the evolution of signaling cascades, making them the weakest links in cellular circuits.
... Conceivability and the Metaphysics of Mind JOSEPH LEVINE North Carolina State University Intr... more ... Conceivability and the Metaphysics of Mind JOSEPH LEVINE North Carolina State University Introduction. ... Page 3. CONCEIVABILITYAND THE METAPHYSICS OF MIND 451 ...
... attack, allegedly to stop rocket attacks launched by Hamas, the governing authority in Gaza. ... more ... attack, allegedly to stop rocket attacks launched by Hamas, the governing authority in Gaza. ... boycott of South Africa during the apartheid era, and I support the imposition of sanctions against Israel, and Israeli companies, in order to secure its withdrawal from ...
Amherst I'm looking at the snowy woods behind my house through the window. I see the (still) whit... more Amherst I'm looking at the snowy woods behind my house through the window. I see the (still) white snow on the ground, the grayish/brownish trunks of the trees, and the dark green needles. The sky is bright and blue. I have had my two morning cups of coffee, so I'm as awake as I ever am. I am having a conscious visual experience, and the conditions are as propitious for veridical perception as they can be. Though a skeptic could engender doubts if I let her, I am morally certain that I am indeed consciously seeing snow, trees, and sky. No doubt about it. Let "E" be the conscious visual experience I just described, which I am having as I write these words. It is natural to think of E as a state I'm in, a mental state-an occurrent mental state. Another natural thing to say, though it now has a technical ring to it, is that "there is something it's like for me to occupy state E". The point is, I occupy many states right now, and for most of them there is nothing it is like to occupy them. Some of these states there is nothing it is like for me to occupy are even occurrent mental states. For instance, I occupy the state of having certain visual receptors fire, or of certain language center modules assigning thematic roles to the constituents of the sentences I am now formulating. Unaware of these processes and states as I am, there is nothing it is like for me to occupy them. But when it comes to the conscious visual experience, clearly there is something it's like for me. What it's like for me to have this conscious visual experience it's now common to call its "phenomenal character". We can thus think of phenomenal character as the answer to the question, "what is it like for you to see what you see now?" Now, in general, if someone asks what X is like-whether it be an object, event, or state-the answer, that it is like P, seems to involve predicating a property of X. "What is your dog like? She's very friendly." I'm claiming that
How do we imagine these sensory qualities being instantiated in experiences? Clearly, on Clark’s ... more How do we imagine these sensory qualities being instantiated in experiences? Clearly, on Clark’s account, for a sensory quality to be instantiated in an experience is for the brain to occupy a certain state. The question then becomes how the brain’s states count as realizing the relevant quality space, so that any one state can be mapped onto a location in that space. Well, there are two possibilities. First, if brain states maintained relations of similarity that respected the topology of the color quality space, that would justify mapping individual states onto their respective locations in that space. But of course that isn’t likely, or what I imagine Clark has in mind. There isn’t going to be any well-defined notion of neural similarity that will
The present paper deals with three sources of holistic arguments: confirmation of scientific theo... more The present paper deals with three sources of holistic arguments: confirmation of scientific theories, translation between languages, relationships between belief, meaning and reference. Confirmation holism (CH), belief holism (BH) and meaning holism (MH) are the main theses to be examined. However, the various topics are thought of as instrumental to the clarification of MH, a position whose identification depends on the status assigned to meanings. To fix ideas, MH can be taken as saying that the meaning of any sentence (or term) is given by the totality of its semantic links, thus, in order to talk about its meaning, a wide set of other sentences (terms) is required, yet there is no definite set of such sentences, it's always a jigsaw puzzle of interpretation, where each piece has no autonomous meaning.
Siewert's book revolves around three theses: that there is a distinctive style of epistemic w... more Siewert's book revolves around three theses: that there is a distinctive style of epistemic warrant associated with the first-person point of view, that if we pay close attention to the deliverances of this first-person point of view, we will see that phenomenal consciousness is both real and yet neglected by many current theories that purport to explain consciousness, and that phenomenal consciousness is inherently intentional; one cannot divorce what phenomenal character presents to us from what it's like to have it. Among several points made on the relations among these three theses, it is argued that Siewert's argument for the distinctive status of first-person warrant does not provide him with the support necessary to employ that thesis in his defense of the significance of phenomenal consciousness. Siewert's book aims to establish, as the title announces, the "significance" of consciousness. He does this by arguing in great detail for three principal ...
In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, tha... more In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, that pick out individuals, from type-demonstratives, that pick out kinds, or properties, and provide a similar treatment for both. I argue that it follows from my model of demonstrative thought, as well as from independent considerations, that demonstration, as a mental act, operates directly on mental representations, not external objects. That is, though the relation between a demonstrative and the object or property demonstrated is semantically direct, the mechanism by which a demonstrative acquires its referent involves mediation by a perceptual representation. Finally, I argue that so-called 'demonstrative concepts'-which I treat as type-demonstratives-cannot perform the various philosophical functions that have been assigned to them.
Background-Ventricular tachyarrhythmias long enough to cause implantable cardioverter defibrillat... more Background-Ventricular tachyarrhythmias long enough to cause implantable cardioverter defibrillator (ICD) shocks are generally thought to progress to cardiac arrest. In previous ICD trials, shocks have been considered an appropriate surrogate for sudden cardiac death (SCD) because the number of shocks has been thought to be equivalent to the mortality excess in patients without ICDs. The practice of equating ICD shocks with mortality is controversial and has not been validated critically. Methods and Results-The Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial was a prospective, randomized, multicenter trial of ICD therapy in 458 patients with nonischemic cardiomyopathy. Patients were randomized to receive standard medical therapy (STD) or STD plus an ICD. Shock electrograms were reviewed, and the cause of death was evaluated by a separate blinded events committee. There were 15 SCD or cardiac arrests in the STD group and only 3 in the ICD arm. In contrast, of the 229 patients randomized to an ICD, 33 received 70 appropriate ICD shocks. Patients in the ICD arm were more likely to have an arrhythmic event (ICD shock plus SCD) than patients in the STD arm (hazard ratio 2.12, 95% CI 1.153 to 3.893, Pϭ0.013). The number of arrhythmic events when one includes syncope as a potential arrhythmic event was similar in both groups (hazard ratio 1.20, 95% CI 0.774 to 1.865, Pϭ0.414). Approximately the same number of total events was noted in each arm when we compared syncope plus SCD/cardiac arrest in the STD arm with SCD plus ICD shocks plus syncope in the ICD arm. Conclusions-Appropriate ICD shocks occur more frequently than SCD in patients with nonischemic cardiomyopathy. This suggests that episodes of nonsustained ventricular tachycardia frequently terminate spontaneously in such patients.
Covalent modification cycles (e.g., phosphorylation-dephosphorylation) underlie most cellular sig... more Covalent modification cycles (e.g., phosphorylation-dephosphorylation) underlie most cellular signaling and control processes. Low molecular copy number, arising from compartmental segregation and slow diffusion between compartments, potentially renders these cycles vulnerable to intrinsic chemical fluctuations. How can a cell operate reliably in the presence of this inherent stochasticity? How do changes in extrinsic parameters lead to variability of response? Can cells exploit these parameters to tune cycles to different ranges of stimuli? We study the dynamics of an isolated phosphorylation cycle. Our model shows that the cycle transmits information reliably if it is tuned to an optimal parameter range, despite intrinsic fluctuations and even for small input signal amplitudes. At the same time, the cycle is sensitive to changes in the concentration and activity of kinases and phosphatases. This sensitivity can lead to significant cell-to-cell response variability. It also provides a mechanism to tune the cycle to transmit signals in various amplitude ranges. Our results show that signaling cycles possess a surprising combination of robustness and tunability. This combination makes them ubiquitous in eukaryotic signaling, optimizing signaling in the presence of fluctuations using their inherent flexibility. On the other hand, cycles tuned to suppress intrinsic fluctuations can be vulnerable to changes in the number and activity of kinases and phosphatases. Such trade-offs in robustness to intrinsic and extrinsic fluctuations can influence the evolution of signaling cascades, making them the weakest links in cellular circuits.
... Conceivability and the Metaphysics of Mind JOSEPH LEVINE North Carolina State University Intr... more ... Conceivability and the Metaphysics of Mind JOSEPH LEVINE North Carolina State University Introduction. ... Page 3. CONCEIVABILITYAND THE METAPHYSICS OF MIND 451 ...
... attack, allegedly to stop rocket attacks launched by Hamas, the governing authority in Gaza. ... more ... attack, allegedly to stop rocket attacks launched by Hamas, the governing authority in Gaza. ... boycott of South Africa during the apartheid era, and I support the imposition of sanctions against Israel, and Israeli companies, in order to secure its withdrawal from ...
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