Online research in philosophy

The words “content” and “character” in my title refer to the representational content and phenomenal character of color experiences. So my topic concerns the nature of our experience of color. But I will, of course, be talking about colors as well as color experience. Let me set the stage by mentioning some things, some more controversial than others, that I will be taking for granted. I assume, to begin with, that objects in the world have colors, and have them independently of being perceived to have them, and independently even of there being creatures capable of perceiving them. I think, and this of course sets me apart from the many color irrealists among philosophers and color scientists, that any reasonable semantics for color terms, and any reasonable account of the reference of color concepts, should yield the result that colors are properties of external things that are realized in certain of their physical properties, namely those responsible for their reflecting or emitting the light whose impact on our retinas is involved in causing our color perceptions. This brings me to a further assumption that I shall be making, namely the truth of physicalism. I take physicalism to be the thesis that all properties of things either are or are realized in basic physical properties, where basic physical properties are the properties that underlie the behavior and causal powers of inanimate things. There are two ways in which the commitment to physicalism will figure in my discussion. First, I assume that colors are physically realized properties. Second, I assume that color experiences are physically realized. These two commitments frame the problem I am discussing – how can colors be properties realized in the microphysical properties of things, and how can color experience be so realized? I don’t think there is any generally accepted account of what it is for a property to be “realized in” other properties. For those who think, as I do, that properties are individuated by their causal features, it should seem plausible to say that property P realizes property Q just in case the forward looking causal features of Q are a subset of the forward looking causal features of P, and the backward looking....

Prospective memory is required for many aspects of everyday cognition, its breakdown may be as debilitating as impairments in retrospective memory, and yet, the former has received relatively little attention by memory researchers. This article outlines a strategy for changing the fortunes of prospective memory, for guiding new research to shore up the claim that prospective memory is a distinct aspect of cognition, and to obtain evidence for clear performance dissociations between prospective memory and other memory functions. We begin by identifying the unique requirements of prospective memory tasks and by dividing memory's prospective functions into subdomains that are analogous to divisions in retrospective memory (e.g., short- versus long-term memory). We focus on one prospective function, called prospective memory proper; we define this function in the spirit of James (1890) as requiring that we are aware of a plan, of which meanwhile we have not been thinking, with the additional consciousness that we made the plan earlier. We give an operational definition of prospective memory proper and specify how it differs from explicit and implicit retrospective memory and how it might be empirically assessed.

Thomas Polger and Lawrence Shapiro (or P&S) have recently (2008) criticized ?causal-mechanist? views of realization that dominate research in the philosophy of mind and metaphysics of science. P&S offer the internal criticism that any account of realization focusing upon property instances, as views of causal-mechanist realization routinely do, must lead to incoherence about multiple realization. P&S's argument highlights important issues about property instances that have recently been neglected, as well as raising a challenge to the standard approach to understanding the non-causal relations between properties and their instances in the sciences. In response, I clarify some important background issues about property instances and their relations to properties which show why P&S's main argument fails. In addition, I provide a second reason to doubt their argument by highlighting reasons to think that instances, as well as properties, are plausibly sometimes multiply realized in the sciences.

Single-unit data from the cortex of monkeys performing working-memory tasks support the main point of the target article. Those data, however, also indicate that the activation of long-term memory is essential to the processing of all cognitive functions. The activation of cortical long-term memory networks is a key neural mechanism in attention (working memory is a form thereof), perception, memory acquisition and retrieval, intelligence, and language.

We discuss the role of short-term auditory verbal storage within a working memory system. Data from single case studies of patients with left parietal lesions and selective impairment of memory span are discussed in order to address the question of the functions of short-term memory in language processing. The backup resource of auditory verbal short-term memory is required for those tasks that necessitate backtracking in order to integrate a verbal message within a developing central cognitive representation.

Neural models have proposed how short-term memory (STM) storage in working memory and long-term memory (LTM) storage and recall are linked and interact, but are realized by different mechanisms that obey different laws. The authors' data can be understood in the light of these models, which suggest that the authors may have gone too far in obscuring the differences between these processes.

One theme in recent philosophical attention to neuroscience has been that closer, more serious attention to actual neuroscientific research, and its results, challenges the familiar view that psychological properties are multiply realized by neuroscientific properties. Shagrir, (1998), presents a number of diverse reasons to think that diversity in neuroscientifically identified structures and properties does not inevitably lead to multiple realization. Bechtel and Mundale, (1999), argue that neuroscientific practice extending over a century contradicts the consequences of the hypothesis that psychological functions are multiply realized. Bickle, (2003), argues that a series of animal models of the consolidation of short-term memories into long-term memories reveals that this process is uniquely realized by a single biochemical cascade involving cAMP, protein kinase A, and cAMP response element binding proteins. Shapiro, (2004), argues that experiments on neuroplasticity do not show that there are many ways in which a brain might be wired in order to achieve a given psychological function.

Some scientists and philosophers have claimed that there is a converse to multiple realizability. While a given higher-level property can be realized by different lower-level properties (multiple realizability), a given lower-level property can in turn serve to realize different higher-level properties (this converse I dubbed the unfortunately obscure "constructival plasticity" to emphasize the constructive metaphysics involved when realizing properties generate realized properties in the stated way). I begin by defining multiple realizabilty in a formal way, then turn to the relation in question. By my analysis, for the converse claim to be true, a lower-level property G1 that realizes a higher-level F must be taken in conjunction with some other base condition G2 so that a difference in G2 allows G1 to determine some other higher-level property E but not F (otherwise there would be violations of supervenience). The realization law thus has the form: (G1 & G2) => F. As such, the base property G1 is insufficient by itself to produce F. It is an insufficient but necessary part of a sufficient condition. I also point out that this makes the realization base property an INUS condition, if combined with multiple realizability. Specifically, if F is multiply realized by properties other than the pair G1 and G2, then G1 is an insufficient but necessary part of an unnecessary but sufficient condition.

It is a common assumption in contemporary cognitive neuroscience that discovering a putative realized kind to be dissociably realized (i.e., to be realized in each instance by two or more distinct realizers) mandates splitting that kind. Here I explore some limits on this inference using two deceptively similar examples: the dissociation of declarative and procedural memory and Ramachandran's argument that the self is an illusion.

Suppose that scientists discover a high level property G that is prima facie multiply realized by two sets of lower level properties, F1, F2, …, Fn, and F*1, F*2, …, F*m. One response would be to take this situation at face value and conclude that G is in fact so multiply realized. A second response, however, would be to eliminate the property G and instead hypothesize subtypes of G, G1 and G2, and say that G1 is uniquely realized by F1, F2, …, Fn, and that G2 is uniquely realized by F*1, F*2, …, F*m. This second response would eliminate a multiply realized property in favor of two uniquely realized properties.1 Clearly these are two logically possible responses to this type of situation, so when faced with it how do scientists respond in real cases? This is a matter of providing a descriptively adequate account of actual scientific practice. In support of the view that scientists opt for the “eliminate-and-split” strategy, one might propose that it is illustrated by the way scientists responded in the case of memory. Once upon a time, it was thought that there existed a single kind of memory. With the advance of science, however, it was discovered that it is possible to perform certain sorts of brain lesions that would lead to the selective loss of certain memory functions, while certain other sorts of brain lesions would lead to selective loss of certain other memory functions. These neurobiological dissociation experiments, one might say, support the view that, instead of a single overarching type of memory, there are distinct subtypes of memory.