Explanatory power

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). 

Although electronic configurations are traditionally invoked to explain the periodic system, their explanatory power remains only approximate... 

But aside from its explanatory power is there any historical evidence for the truth of this account And, in particular, is there evidence for the precise pro-predictivist claims 1 and 2 on which it is—-somewhat shakily—built ... 

Woody, A. (1995). The explanatory power of our models A philosophical analysis with some implications for science education. In F. Finley, D. Allchin, D. Rhees, S. Fifields (Eds.),Proceeding of the third international history, philosophy, and science teaching conference (Vol. 2. pp. 1295-1304). Minneapolis University of Minnesota. 

Arguing against the causal efficacy of some disjunctive properties, Sober has held that disjunctive properties will appear to be causally efficacious only to the degree that their disjuncts strike us as subsuming similar sorts of possible causal processes (Sober, 1984, p. 94). Suppose we drop out the qualifications will appear to be and strike us as unsuited to a question about whether disjunctive properties really are causally efficacious as opposed to seeming to us to be causally efficacious. If we adopt this principle, the question at issue becomes one of whether the disjunction of Pi, v P2v... v P,, v... v Pm subsumes similar sorts of causal processes, to which the answer seems to be that the disjunction shares in common the features of having been selected for resulting in the same outcome, i.e. PS-processes. Thus, the disjunctive predicate names a causal property, a natural kind. Antireductionists are hard pressed to deny the truth and the explanatory power of (R). 

Murray treats his sets of simultaneous equations not as generalizations with independent explanatory power, but as parts of a how-possibly explanation which needs to be cashed in by developments which convert it into a why-necessarily explanation or supplant it with such an explanation. 

To see why we can have explanatory power without predictive power, consider once again the redurtion of cognitive dissonance. In many people, this mechanism coexists with the exactly opposite one, captured in homely sayings such as "The... 

Conversely, we may have predictive power without explanatory power. To predict that less of a good will be bought when its price goes up, there is no need to form a hypothesis about consumer behavior. Whatever the springs of individual action -rational, traditional or simply random - we can predia that people will buy less of the good simply because they can afford less of it. Here there are several mechanisms that are constrained to lead to the same outcome, so that for predictive purposes there is no need to decide among them. Yet for explanatory purposes the mechanism is what matters. It provides understanding, whereas prediction at most offers control. ... 

This, in a nutshell, is what science is all about—it is a process by which new ideas are created to help explain what we observe in nature, both out-of-doors and in the laboratory. The new idea with its explanatory powers is called a hypothesis. The hypothesis is a scientific hypothesis when, and only when, it can be tested. The more tests that the scientific hypothesis passes, the greater the confidence we have that the hypothesis is true. However, if the hypothesis fails even one test, then the hypothesis is taken to be false. A new, more all-encompassing idea is needed. 

A THEORY IS A SINGLE IDEA THAT HAS GREAT EXPLANATORY POWER... 

The barrier that the reaction must overcome in order to proceed is determined by the difference in the solvation of the activated complex and the reactants. The activated complex itself is generally considered to be a transitory moiety, which cannot be isolated for its solvation properties to be studied, but in rare cases it is a reactive intermediate of a finite lifetime. The solvation properties of the activated complex must generally be inferred from its postulated chemical composition and conformation, whereas those of the reactants can be studied independently of the reaction. This is the reason why very little predictive information can be obtained, even though the explanatory power of the transition state theory is very considerable. For organic nucleophilic substitution reactions,... 

Below are five illustrative examples of the explanatory power of classical physics in structural chemistry. In these examples, classical electrostatic interactions are used with the electron-domain representation of molecules to explain or to derive The New Walsh Rules , the Langmuir-Pauling and Hendricks-Latimer Occupancy Rule, the s-character Rule, the Methyl Group — Tilt Rule, and the Octet Rule. 

A significant simplification in the electronic interpretation of chemistry can, in fact, be achieved by introducing the Exclusion Principle at the very beginning of the discussion 153>. The justification for this procedure lies chiefly in the simplicity of the results, their visualizable character, and their explanatory power. 

Chemical affinity is a concept that has been around for a long time but has kept changing. For centuries, it signified the attraction of similar substances for one another. Then it shifted to mean the attraction of opposite or unlike substances. In the seventeenth century, chemists invoked the fit of geometrical shapes and then Newtonian attraction to account for the way that different chemical substances had diverse but distinct attractions for one another. In the early eighteenth century, especially in France, affinity became a central organizing theory for classifying chemical substances and their reactions, but many chemists were reluctant to allow the concept of affinity any explanatory power. 

Evolution is very possibly not, in actual fact, always gradual. But it must be gradual when it is being used to explain the coming into existence of complicated, apparently designed objects, like eyes. For if it is not gradual in these cases, it ceases to have any explanatory power at all. Without gradualness in these cases, we are back to miracle, which is simply a synonym for the total absence of explanation.25... 

At first sight, this poses a fatal dilemma for internal realism. On the first hom of the dilemma we face organizational metaphysical realism. It claims that there are numerous conceptual schemes and they do not simply copy the structure of reality. Such copying would not even be possible, since we do not have direct access to that inherent structure. Rather, the human mind actively projects structures into reality it introduces distinctions, sets up similarity relations, etc. However, there are external constraints on the construction of conceptual schemes, and these constraints are afforded by the inherent structure of reality. Some schemes cut at the joints more often than the others. Failures to cut at the joints are manifested in bad or inaccurate predictions, lack of explanatory power, repeated failures, etc. This view does provide the external constraints necessary for the objectivity of knowledge, and also makes room for the active organizing role of the intellect. But the price is... 

The limitations of the traditional Poisson-Boltzmann treatment are numerous. A particularly important one refers to specific ion effects. The amphoteric latex particles coagulate when the concentration of CsN03 is approximately 1 M, but remain stable at high pH values even when the concentration of KN03 exceeds 3 M [6]. Nevertheless, in the traditional Poisson-Boltzmann approach the double layer repulsions for Cs and K are the same. A number of attempts were made to include additional interactions in the formalism, some of them being briefly discussed in the first part of this article [7], With these corrections, many of them dependent on unknown parameters, the modified Poisson-Boltzmann approach regained its explanatory power, and in general most of the experiments could be accounted for... 

Finally, steric effects also contribute. Thus it seems wiser at this stage to consider empirical substituent effects as an unseparable whole. Relationships like the barrier-electronegativity "correlation shown in Fig. 4 are at best crude empirical leads without physical explanatory power, but which may nevertheless be of some pratical use. 

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