Reduction explanatory

No science is simple, but some are more accessible than others. For comparatively simple, vivid, and diverse illustrations of representation, classification, reduction, explanatory strategies, approximation, formalization, computation, discovery methods. 

As to the general issue of reduction, chemists would do well to consider the work of philosophers of science, who have for some time renounced the notion that any particular branch of science may be strictly reduced to a more basic science. The classic work giving conditions for strict reduction is by Nagel (53), and several detailed criticisms of his views have been published (54, 55). More recently there appears to be a partial return to reductionism under the guise of supervenience . Chemistry is said to supervene over physics even though it cannot be shown to be strictly reducible in the sense of Nagel. Whether supervenience represents merely a hope and whether it holds any explanatory power is the focus of much current work in philosophy (56-58). 

FIG. 11.1. Reductionism, explanatory and heuristic. The left side illustrates the classical view of theory reduction as an explanatory relation, while the right side illustrates the heuristic use of theory reduction in the text. Highlighted items are those whose discovery drives reduction. In explanatory reduction, the reducing and reduced theories (reductans and reductandum) are in hand and the discovery of bridge principles completes the reduction. In heuristic reduction, the reductandum and invariance principles are in hand and the goal is construction of a reducing theory... 

Food Consumption. Food consumption is typically measured with one or two uses in mind. First, it may be explanatory in the interpretation of reductions (either absolute or relative) in body weight. In cases where administration of the test... 

To decarboxilate tyrosine into tyramine, heat the tyrosine with barium hydroxide and separate, as seems practical (several ways are possible) to you. It will be easy to understand once you perform this operation, as it is really quite self-explanatory. Purify as described in JACS, 72, 2781 in the reductions chapter. 

I look at two rival decision-theoretic approaches to addiction and discuss them in the perspective of whether they can be said to represent addiction as a reduction in our ability to exercise of free will. These theories typically use time discounting as the central explanatory mechanism, and in that sense they use something we might see as an impairment in the capacity for rational self-govemance to explain... 

Explanatory approaches to addiction typically concentrate on attitudes to value over time in order to get the explanatory machinery going. The upshot is that people who are prone to addiction are in a way not fully free to begin with. Still, becoming addicted should be represented as a further reduction in freedom, a reduction that does not occur in those who do not consume enough to become addicted. 

Although Table I is generally self-explanatory, the carbonaceous material measurements require comment. Because of its chemical complexity, carbonaceous material is frequently characterized only on the basis of carbon measurements. These measurements attempt to divide the carbonaceous material into organic C and elemental C . Carbon present in carbonate salts, frequently a minor contributor to the total particulate carbon, can be determined independently. Elemental carbon is among the most important pollutants in visibility reduction. Polycyclic aromatic hydrocarbons (PAHs) are relatively minor constituents of the particulate carbon but are of great interest in health effects studies. PAHs can also serve as model compounds in developing improved sampling techniques for semivolatile carbonaceous materials. 

A close look at the place of time within chemistry raises questions about that science s fundamental conceptual and explanatory entities. Put very simply, what is chemistry about A conventional narrative depicts chemistry, in its youth a science of substances, as reaching maturity when it metamorphosed into a science of molecules. The development of transition-state theory certainly conforms to and reinforces that narrative because the theory s successes can be ascribed to its "reduction of the dynamics problem to the consideration of a single structure" (Truhlar et al., 1983, p. 2665). Yet questions have been raised recently as to whether molecular explanations are adequate to account for all chemical phenomena (Woolley, 1978 Weininger, 1984), and the view that substances are still the primary subject matter of chemistry has by no means disappeared (van Brakel, 1997). I suggest that chemists can call on a variety of explanatory entities that are intermediate between the molecule and the substance, and these entities need not have the permanence of either molecules or substances. 

Its first aim is an explanatory one, usually that of connecting successor theories, in particular to provide an explanation of the continuous process of scientific growth, rationalization, and formalization. Such "synchronic" or "intralevel" reduction will not further concern us, however. 

Explanatory reduction concerns the question of whether for every event or process in S there is some mechanism belonging to B which (causally) explains the event or process. 

No strict separation between ontology and ideology, i.e., between things and, properties no strict distinction between ontological, epistemological, and explanatory reduction, and no strict distinction between ontological reduction and conceptual autonomy... 

And yet, a theology comfortable with explanatory pluralism will still encourage all the sciences to push their own purely natural, and inevitably reductive, explanations as far as possible at their own appropriate levels of investigation. Good... 

It is relatively easy to talk and gesture about how chemistry either does or does not reduce to physics. It is much harder to spell out exactly what is required to make good on the claim that chemistry does (or does not) reduce to physics. Philosophers have a concept of supervenience. In the case we are focused on here chemistry putatively reducing to physics—supervenience requires that every chemical change be accompanied by a physical change. This is nearly universally held, for example, if two molecules are identical in all physical respects, they will not differ chemically. However, supervenience is not sufficient for the reduction of chemistry to physics. There could be downward causation, where it is the chemical facts and laws that drive the physical facts and laws, not the other way around. Robin Hendry (Chapter 9) argues that those committed to the reducibility of chemistry to physics have not ruled out the possibility of downward causation, and moreover, he presents substantial evidence from the manner in which quantum mechanical descriptions for molecules are constructed and deployed by chemists in favor of downward causation. Quantum mechanical descriptions of molecules that have explanatory and descriptive power are constructed from chemical—not physical—considerations and evidence. Here in precise terms, we see chemistry supervenient on physics, but still autonomous, not reducible to physics. 

R) The explanatory premises of a reductive explanation of a phenomenon involving property F (e.g. an explanation of why F is instantiated on this occasion) must not refer to F (Kim 2005 105). 

The color green is surely multiply-realizable with respect to the microphysical constitution of all the different possible pigments of green. Even if we could somehow find a way to reduce the color green to microphysics, it still seems like we would lose explanatory power in the reduction. What makes the inductive inference a good one is how well survival is explained by color and how well color can predict future survival. We are not required to know every detail at the microphysical level to make successful predictions. Furthermore, it seems that even if we knew all the lower-level detail, we could fail to make a successful prediction if we did not see the higher-level property eolor as causally relevant. 

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