suggested understanding higher-level causal powers as simply more general and abstract characterizations of the lower-level causal powers implemented in the physical structure of a system. There are many varieties of causal taxonomy classifying things according to various kinds of causal powers they possess. For example, a taxonomy of orbiting bodies may specify the causal powers of objects in terms of mass, position and velocity – abstracting from the body's chemical composition, geology or microbiotic agglomerations. Such an abstract and incomplete characterization of the causal powers of a system makes it possible to group together physically type-distinct instances of the higher-level kind (in this case, planets, stars and other orbiting bodies). Moreover, taxonomies in computer science are typically characterized by such abstractions. What is of interest at the level of information processing are such things as registers and microprogramming operations, not the causal powers of the material structure of semiconductors. Works "Holism without tears: Local and global effects in cognitive processes", Philosophy of Science. 1989. "Marr's three levels: A re-evaluation", Minds and Machines. 1991. "Irreducibility and subjectivity", Philosophical Studies. 1992. "Emergence unscathed: Kim on multiple realizability and causal types", Electronic Journal of Analytic Philosophy. 1992. "Methodological individualism considered as a constitutive principle of scientific inquiry", Philosophical Psychology. 1992. "Functional analysis and etiology", Erkenntnis. 1993. (with Bonnie Steinbock), "When is birth unfair to the child?", in Hastings Center Report. 1994. Existential Cognition: Computational Minds in the World. University of Chicago Press. 1995. "Screening off and the levels of selection", Erkenntnis. 1996. "Modularity", in The Encyclopedia of Cognitive Science. 2003. References External links Faculty page 20th-century American philosophers 21st-century American philosophers American philosophy academics Analytic philosophers American consciousness researchers and theorists Environmental philosophers Epistemologists Existentialists Living people Metaphysicians Ontologists Phenomenologists Philosophers of mind Philosophers of psychology Philosophers of science Philosophy writers University at Albany, SUNY faculty Year of birth missing (living people) 20th-century American male writers 21st-century American male writers