Theories, and the Scientific Method

When a hydrogen halide adds to an alkene, hydrogen adds to the carbon of the alkene that has the greater number of hydrogens attached to it, and the halogen to the carbon that has the fewer hydrogens. 

The first of these statements is close to the way Vladimir Markovnikov expressed it in 1870 the second is the way we usually phrase it now. These two statements differ in an important way—a way that is related to the scientific method. 

Adherence to the scientific method is what defines science. The scientific method has four major elements observation, law, theory, and hypothesis. 

Most observations in chemistry come from experiments. If we do enough experiments we may see a pattern running through our observations. A law is a mathematical (the law of gravity) or verbal (the law of diminishing returns) description of that pattern. Establishing a law can lead to the framing of a rule that lets us predict the results of future experiments. This is what the 1870 version of Markovnikov s rule is a statement based on experimental observations that has predictive value. 

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Rules, Laws, Theories, and the Scientific Method 237 Ethylene and Propene The Most Important Industrial Organic Chemicals 263... 

The scientific method, as mentioned, involves observation and experimentation (research) to discover or establish facts. These are followed by deduction or hypothesis, establishing theories or principles. This sequence, however, may be reversed. The noted twentieth-century philosopher Karl Popper, who also dealt with science, expressed the view that the scientist s work starts not with collection of data (observation) but with selection of a suitable problem (theory). In fact, both of these paths can be involved. vSignificant and sometimes accidental observations can be made without any preconceived idea of a problem or theory and vice versa. The scientist, however, must have a well-prepared, open mind to be able to recognize the significance of such observations and must be able to follow them through. Science always demands rigorous standards of procedure, reproducibility, and open discussion that set reason over irrational belief. 

The scientific method is taught starting in elementary school. The first step in the scientific method is to form a hypothesis. A hypothesis is just an educated guess or logical conclusion from known facts. It is then compared against all available data and its details developed. If the hypothesis is found to be consistent with known facts, it is called a theory and usually published. The characteristics most theories have in common are that they explain observed phenomena, predict the results of future experiments, and can be presented in mathematical form. When a theory is found to be always correct for many years, it is eventually referred to as a scientific law. However useful this process is, we often use constructs that do not fit in the scientific method scheme as it is typically described. 

A theory is our best present interpretation of why things happen the way they do The modern ver Sion of Markovnikov s rule which is based on mecha nistic reasoning and carbocation stability recasts the rule in terms of theoretical ideas Mechanisms and explanations grounded in them belong to the theory part of the scientific method... 

It IS worth remembering that a theory can never be proven correct It can only be proven incor rect incomplete or inadequate Thus theories are always being tested and refined As important as anything else in the scientific method is the testable hypothesis Once a theory is proposed experiments are designed to test its validity If the results are con sistent with the theory our belief in its soundness is strengthened If the results conflict with it the theory IS flawed and must be modified Section 6 7 describes some observations that support the theory that car bocations are intermediates in the addition of hydro gen halides to alkenes... 

Laurent, Gerhardt, and the Philosophy of Chemistry," HSPS 6 (1975) 405429, and "Methods and Methodology in the Development of Organic Chemistry," Ambix 34 (1987) 147155 Rocke, "Kekule s Benzene Theory and the Appraisal of Scientific Theories," 45161, in A. Donovan et al., eds., Scrutinizing Science (Dordrecht Kluwer Academic Publishers, 1988). On Kuhnian vs. Popperian models, see H. W. 

Rational control of health and environnental risks from technical development requires scientific knowledge which must be acquired through the orderly process of the scientific method of inquiry. Contrary to widely held opinions the latter is no less subjective than other rational human endeavors which require decisions under uncertainty. Indeed, to be applied, the method requires a value system which in ordinary research is supplied by the various scientific disciplines. Because of differences among the disciplinary value systems problems often arise in the interdisciplinary settings of efforts to control risks from technical development. Metrics, the concepts, theory, and practice of measurement is suggested here as a way to deal with such problems. 

Because of the nature of the scientific method. Metrics is an indispensable tool of scientific research. It can provide rigorous indices of the internal consistency and the predictive power of "accepted knowledge" about study systems. Thus, it can aid with theory testing. It can also provide rigorous indices of the strength of correlations between the attributes of the study system and the external factors that might influence it. Thus, it can assist with statistical hypothesis formulation and testing. 

My story is a peculiar one. It is hard to know what to make of it. The notion of some kind of fantastically complicated visionary revelation that happens to put one at the very center of the action is a symptom of mental illness. This theory does that, and yet so does immediate experience, and so do the ontologies of Judaism, Islam, and Christianity. My theory may be clinically pathological, but unlike these religious systems, I have enough humor to realize this. It is important to appreciate the intrinsic comedy of privileged knowledge. It is also important to have recourse to the scientific method whenever appropriate. Most scientific theories can be disproven in the calm confines of the laboratory, evolution to the contrary. 

Abstract. In this paper, we advocate the use of literate programming techniques in molecular physics and quantum chemistry. With a suitable choice of publication medium, literate programming allows both a theory and corresponding computer code to be placed in the public domain and subject to the usual open criticism and constructive use which form an essential ingredient of the scientific method. 

Hypothesis In a scientific investigation, a tentative explanation of observations in a laboratory or nature. Hypotheses are then tested with the scientific method to determine their validity. If a hypothesis is highly reliable at explaining and even predicting a phenomenon, it becomes a theory. 

A recent book on physical chemistry,5 written by a scientist6 and aimed primarily at other scientists, contains substantial historical information on the beginnings of physical chemistry and on various topics, such as chemical spectroscopy, electrochemistry, chemical kinetics, colloid and surface chemistry, and quantum chemistry. The book also discusses more general topics, such as the development of the physical sciences and the role of scientific journals in scientific communication. The same author has written a brief account of the development of physical chemistry after 1937,7 emphasizing the application of quantum theory and the invention of new experimental methods stopped-flow techniques (1940), nuclear magnetic resonance... 

Robert Boyle was educated in alchemy in the mid-1600s, but he published a book called The Skeptical Chemist that attacked alchemy and advocated using the scientific method. He is sometimes called the founder of modern chemistry because of his emphasis on proving a theory before accepting it, but the birth of modern chemistry is usually attributed to Lavoisier. Boyle rejected the 4 classical elements and proposed the modern definition of an element. Boyle s law states that gas volume is proportional to the reciprocal of pressure. 

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