Introductory Physics by Herbert Priestley (Allyn and Bacon, Inc., 1958) has one of the best presentations of physics I’ve ever seen. (The book is, sadly, out of print and hard to find.) He presents concepts in their historical and scientific context. Priestley presents alternative viewpoints that were being used to understand phenomena such as heat or electricity, discusses why each viewpoint was held and the arguments scientists had on which position was right, and describes in some detail the experiments scientists did – especially the experiments which validated one side or the other. In showing us the development of ideas in physics, Priestley is showing us the correct view of concept formation and the formation of generalizations, Priestley is showing us that true concepts and propositions come from applying rational, objective methods to the real world.
Priestley attended the University of Leeds, receiving a B.S. in 1933 and a Ph.D. in physics in 1935. He served in the Royal Air Force as an industrial research physicist, civilian education officer, and air intelligence officer. He came to the US as RAF liaison officer in 1942, but stayed on to teach physics at Ripton College after WWII. In 1952, he became chairman of the physics department at Knox College, where he stayed until he retired in 1980. His obituary is on Knox College‘s Website.
Two caveats. Priestley makes some statements in his Chapter 1 about the philosophy of science which I do not fully agree with. He also does not give Aristotle proper credit as a scientist. People have insulted Aristotle for centuries, for things that are not Aristotle’s fault –- there have been people throughout history who blindly believed what was written in Aristotle’s corpus and who did not look at reality on their own, yes, but that is not Aristotle’s fault. Aristotle, in method, was objective, and referred to experience. If he had the evidence available to him which people did who lived 1,000 years or more after he lived, he could have arrived at the conclusions modern scientists have. He was a solid scientist, as can be seen in the work he did most: philosophy, logic and biology.
Dr. James Lennox, Professor of Philosophy and the History of Science at the University of Pittsburgh, has some good articles on his Website regarding Aristotle as scientist and philosopher of science. An article directly relevant to some of Priestley’s uninformed, unresearched accusations against Aristotle is Lennox’s “Aristotle, Galileo and the Mixed Sciences,” which discusses (1) Aristotle’s use of mathematics as a tool of explanation and (2) Galileo’s debt to Aristotle.
Following is an excerpt from Priestley’s book. I hope this is not a copyright violation! (This post is a great advertisement for the book. This post publicizes and praises the book, which would otherwise remain largely unknown. Plus, while the quoted section is lengthy, it is a small percentage of the whole.) The book is out of print, but, I think, still under copyright. I communicated with the publisher, who said they did not have any copies of the book to sell and would not make any. This is a book that should be reprinted! It should be preserved, studied, spread far and wide, and used as a standard for how science textbooks should be.
It is impossible to grasp Priestley’s masterful and rational approach in brief one-paragraph excerpts, so the excerpt must be lengthy. Priestley does use math (only algebra; no calculus) in his textbook, but the excerpt has none. The excerpt illustrates, in context of electricity, how Priestley focuses his discussion of physics on causality, scientific method, and the development of concepts, principles and theories.
Excerpt Chp. 15, “Electricity and Chemistry,” pp. 201-205
15.1 Galvanism. Electricity and chemistry are closely inter-related. A chemical reaction can produce a supply of electricity for as long as the reaction continues. This, the first source of a continuous supply of electricity, an electric current, is the principle of the electric battery. Conversely, an electric current can produce a chemical reaction, usually the decomposition of a chemical compound into its simpler elements, the process of electrolysis. Both processes involve the conversion of energy from one form to another; in the first case, chemical energy becomes electrical energy; in the other, the reverse takes place.
Every living cell produces electricity. The functioning of living tissue today is studied through its electrical action. The study of electricity in living tissue, which began quite accidentally about one hundred and fifty years ago, led to the development of the electric battery, for many years thereafter the standard method of producing electricity
About 1750, it was noted that pieces of lead and silver placed above and below the tongue, respectively, with their outer edges in contact, produced an unpleasant and pungent taste not encountered when the metals were placed separately upon the tongue. The phenomenon was attributed to some excitation of the nerves of the tongue. By this time, various physicians and experimenters had demonstrated that electricity could be used as a muscular stimulant in man and animals. This fact had been used to distinguish between paralyzed and atrophied muscles, an electric charge producing a contraction only in a paralyzed muscle.
Before the end of the eighteenth century it was known that an electric discharge passed through the body of a freshly killed animal could cause a convulsive action in its muscles, and that the discharge of an electric eel (section 14.2) produced motion in a nearby dead fish. Identification of the origin of these effects was made by Galvani (1737-1798), a professor of anatomy at Bologna. Galvani began experimenting about 1780, using a Leyden jar [A Leyden jar was the earliest form of electric condenser, consisting of “a bottle filled with water into which was inserted a wire held in place by a cork.” p. 191] and an electrostatic machine to test the effects of the electric discharge upon the nervous system of the frog. During these experiments he made the chance observation that nearby electrical discharge caused convulsions in a freshly prepared frog’s leg in conducting contact with the earth.
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