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Benjamin Franklin's 10 Basic Hypotheses

Benjamin Franklin's 10 Basic Hypotheses

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February 22, 2012

Sidebar article to: " Benjamin Franklin: Enlightenment Archetype "

1. Electrical matter consists of extremely small particles. (True. Electrons are particles and are smaller than can be measured.)

2. Electrical matter is a single fluid, not two. (True, if one considers that the phenomena observed in the electrostatic experiments of the eighteenth century involved only the movement of electrons, not the movement of positively charged ions.)

3. In light of Point 2, opposite electrical charges are to be explained by an excess and defect of electrical matter. (True, if one thinks of electricity as consisting only of electrons. Unfortunately, Franklin [as he understood] had no way to determine which of the two electrical states represented an excess of electrical particles and which a deficiency. He made a fifty-fifty bet-and lost. The state he dubbed negative [thinking it had a deficienc of electrical fluid] is in fact the state that has an excess of electrons. To preserve his language, it has been necessary to establish the convention that the electron has a negative charge and the proton a positive charge.)

4. Electrical matter can be accumulated and discharged but not destroyed. (True. The conservation of charge still stands as an important principle of physics.)

5. The difference between particles of common matter and particles of electrical matter is that the former attract each other (as Newton showed) and the latter repel. (Effectively true-if one thinks of electrical particles as electrons only. Of course, electrons are part of "common matter" and possess gravitational attraction for each other. But the electrical repulsion between two electrons is 4 x 1042 times stronger than the gravitational attraction between them. So, the latter can be ignored.)

6. Generally, common matter contains as much electrical matter as it can hold; if one attempts to add more electrical matter, it accumulates on the surface of the common matter to form an electrical atmosphere. In that case, the common matter is said to be electrified. (Effectively true. Atoms are, in general, electrically neutral. But an atom's outer electrons can be stripped away from it and added to the outer shell of other atoms.)

7. A body that has lost some of its normal quantity of electrical matter attracts the electrical matter in the electric atmosphere of a positively charged body, drawing the two bodies together. (Effectively true. Matter stripped of electrons will tend to attract matter with an abundance of electrons.)

8. Two electrified bodies repel each other because they both have electrical atmospheres made up of particles that repel each other. (A major flaw. Even on Franklin's own terms, this hypothesis would explain only why two "positively charged" bodies repel each other. It could not explain why two "negatively charged" bodies repel each other. The defect in Franklin's theory had to be corrected by Franz Aepinus [1724-1802].)

9. All bodies do not retain electric matter equally; glass and other nonconductors hold it more strongly than metals and other conductors. (True.)

10. Electrical matter is nonetheless present in all matter, because we can always pump some out. (Effectively true. Electrons are present in all neutral atoms.)

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