Mohan Matthen

natural selection may show why all (most, some) humans have an opposable thumb, but cannot show why any particular human has one, Karen Neander ([1995a], [1995b]) argues that this is false because natural selection is 'cumulative'. It is argued here, on grounds independent of its cumulativity, that selection can explain the characteristics of individual organisms subsequent to the event. The difference of opinion between Sober and his critics turns on an ontological dispute about how organisms are identified and individuated. The assumption that Sober needs to make his point is extraneous to population genetics, and, for this reason, gratuitous.

Sound like a philosopher’s controversy? I think so. In ‘Evolution,’ I argued that Anti-Individualism was committed to a ‘highly metaphysical’ proposition at odds with the methodology of population genetics. This infelicity gave me reason for rejecting it. In his recent article, Pust takes issue with Neander and me. Until Pust wrote, Sober felt some small pressure from Individualism, and had shifted, albeit microscopically, toward it—he thought that on a very broad conception of causation, there might be some reason to think that selection explains individual traits. He is now convinced that he was right all along. So we are back where we were a few years ago, though with new arguments on each side. Such is the nature of progress in philosophy. The purpose of this paper is to offer some refinements of Individualism.

Cognitive definitions cannot accommodate fear as it occurs in species incapable of sophisticated cognition. Some think that fear must, therefore, be noncognitive. This paper explores another option, arguably more in line with evolutionary theory: that like other "biological universals" fear admits of variation across and within species. A paradigm case of such universals is species: it is argued that they can be defined by ostension in the manner of Putnam and Kripke without implying that they must have an invariable essence. Emotions can be defined in this way too, in principle, but the theoretical understanding of homology necessary to do so is lacking at present.

What is the relationship between color experience and color? Here, I defend the view that it is semantic: color experience denotes color in a code innately known by the perceiver. This semantic theory contrasts with a variety of theories according to which color is defined as the cause of color experience (in a special set of circumstances). It also contrasts with primary quality theories of color, which treat color as a physical quantity. I argue that the semantic theory better accounts for the kinds of knowledge we have regarding both the color of objects that we see and of the colors themselves.

In this paper I shall examine Aristotle's treatment of a certain puzzle concerning change. In section I, I shall show that within a certain standard framework for the semantics of subject-predicate sentences a number of things that Aristotle wants to maintain do not make sense. Then, I shall outline a somewhat non-standard account of the semantics for such sentences — arguably Aristotle's — and show how the proposals concerning change fit quite naturally into this framework. The results of this exercise will enable us to say something quite precise about applications of some obscure but characteristically Aristotelian doctrines: that ‘is’ is ‘said in many ways,’ that his predecessors got the Law of Opposites wrong. They also shed some light upon Aristotle's ontology of predicables.

Much recent work on Aristotle's Categories assumes that there is an ontological theory presented in that work and tries to reconstruct it on the basis of the slender evidence in the book. I claim that this is misguided. Using a distinction made by G.E.L. Owen between theory and the "phaenomena", I argue that the Categories is mainly concerned with setting out the phenomena -- the intuitions that any ontology must explain. This thesis has consequences for the interpretation of Aristotle's ontological writings. I explore some of these.

This paper presents a new account of aesthetic pleasure, according to which it is a distinct psychological structure marked by a characteristic self-reinforcing motivation. Pleasure figures in the appreciation of an object in two ways: In the short run, when we are in contact with particular artefacts on particular occasions, aesthetic pleasure motivates engagement and keeps it running smoothly—it may do this despite the fact that the object we engagement is aversive in some ways. Over longer periods, it plays a critical role in shaping how we engage with objects to get this kind of pleasure from them. This account is yoked to a broadly functional understanding of art: it is not the nature of the object that makes it art, but the nature of the response that it is designed to elicit. The view does not, however, rest on individual psychology alone, as some other functional accounts do. Crucially, it is argued that shared cultural context is a key determinant of the pleasure we derive from aesthetic artefacts. The pleasure of art is always communal and communicative.

Perceptions "present" objects as red, as round, etc.-- in general as possessing some property. This is the "perceptual content" of the title, And the article attempts to answer the following question: what is a materialistically adequate basis for assigning content to what are, after all, neurophysiological states of biological organisms? The thesis is that a state is a perception that presents its object as "F" if the "biological function" of the state is to detect the presence of objects that are "F". The theory contrasts with causal/informational theories, and with internalist theories, for example those which assign content on the basis of introspected feel. Its advantages are that it permits perceptual error while at the same time allowing content to be expressed in terms of external properties. The argument of the paper is illustrated throughout by examples from biology and computational psychology.

Homeostatic Property Cluster (HPC) theory suggests that species and other biological taxa consist of organisms that share certain similarities. HPC theory acknowledges the existence of Darwinian variation within biological taxa. The claim is that “homeostatic mechanisms” acting on the members of such taxa nonetheless ensure a significant cluster of similarities. The HPC theorist’s focus on individual similarities is inadequate to account for stable polymorphism within taxa, and fails properly to capture their historical nature. A better approach is to treat distributions of traits in species populations as irreducible facts, explained in terms of selection pressures, genealogy, and other evolutionary factors. We call this view Population Structure Theory (PST). PST accommodates the view, implicit in biological systematics, that species are identified by reference to particular historical populations.

Scientists are often bemused by the efforts of philosophers essaying a theory of colour: colour science sports a huge array of facts and theories, and it is unclear to its practitioners what philosophy can or is trying to contribute. Equally, philosophers tend to be puzzled about how they can fit colour science into their investigations without compromising their own disciplinary identity: philosophy is supposed to be an _a priori_ investigation; philosophers do not work in psychophysics labs – not in their professional capacity, anyway

The statistical interpretation of the Theory of Natural Selection claims that natural selection and drift are statistical features of mathematical aggregates of individual-level events. Natural selection and drift are not themselves causes. The statistical interpretation is motivated by a metaphysical conception of individual priority. Recently, Millstein, Skipper, and Dietrich (2009) have argued (a) that natural selection and drift are physical processes, and (b) that the statistical interpretation rests on a misconception of the role of mathematics in biology. Both theses are contested.

Standard biological and philosophical treatments assume that dramatic genotypic or phenotypic change constitutes instantaneous speciation, and that barring such saltation, speciation is gradual evolutionary change in individual properties. Both propositions appear to be incongruent with standard theoretical perspectives on species themselves, since these perspectives are (a) non-pheneticist, and (b) tend to disregard intermediate cases. After reviewing certain key elements of such perspectives, it is proposed that species-membership is mediated by membership in a population. Species-membership depends, therefore, not on intrinsic characteristics of an organism, but on relationship of an organism to others. A new definition of speciation is proposed in the spirit of this proposal. This definition implies that dramatic change is neither necessary nor sufficient for speciation. It also implies, surprisingly, that an organism can change species during its lifetime.

Memory seems intuitively to consist in the preservation of some proposition (in the case of semantic memory) or sensory image (in the case of episodic memory). However, this intuition faces fatal difficulties. Semantic memory has to be updated to reflect the passage of time: it is not just preservation. And episodic memory can occur in a format (the observer perspective) in which the remembered image is different from the original sensory image. These difficulties indicate that memory cannot be preserved content. It is proposed that what is preserved in memory isan underlying "trace", and that in every act of remembering, memorial content is reconstructed from the preserved trace.