Laws of attraction

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For other uses, see: Laws of Attraction (movie); Law of Attraction (new age).

In the history of science, the laws of attraction are a set of assumed laws or, in a sense, a general catch phrase used when discussing the nature of bodies that attract. Historically, the concept of there being a known set of the laws of attraction evolved from the laws of affinity, which numbered up to ten depending upon which chemist was sourced. In c. 390 BC, Plato built on Empedocles’ conception of philia (attractive force) and neikos (repulsive force) by postulating the first law of affinity that “likes tend toward likes” (likes attract), e.g. earth to earth or water to water, etc. In 1250, Albertus Magnus applied the conception of ‘affinity’ to chemical systems and postulated four laws of affinity.

In 1687, Isaac Newton proposed that chemical affinities were due to certain forces that would likely follow similar laws analogous to the three laws of planetary motion. He expanded on these views in ‘Query 31’ of his 1704 Opticks. In 1718, after translating Newton’s Opticks, French physician and chemist Étienne Geoffroy proposed a new law of affinity that ‘whenever two substances are united that have a disposition to combine and a third is added that has a greater affinity with one of them, these two will unite, and drive out the other.’ Using this law, he published the first every affinity tables.

In 1749, building on Geoffroy’s affinity table, French chemist J. P. Macquer published six truths of chemical affinity, which encompassed both Plato’s and Geoffroy’s affinity laws, as well as four new ones. In 1766, he published seven types of affinity in his Dictionnaire de chymie.

In this manner, most consider Isaac Newton to be the one who stimulated the discover of the "laws of attraction". Before this, however, the ancient Greeks knew from magnetic interactions that "opposites attract" and "likes repel". This factor is modeled essentially via Coulomb's law.

In the latter half of the 20th century, the theory of electromagnetism, unified by James Clerk Maxwell in 1873, is the physics of the electromagnetic field; a field encompassing all of space which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. This effect, as modeled via Maxwell's field equations, can be thought of as the electromagnetic laws of attraction and repulsion.

With the discovery of sub-atomic particles, such as the quark (1964), and the fundamental forces, the term "laws of attraction" has been replaced with the conception of field particle exchange, and the boding effect created therefrom. Subsequently, in the 20th century the laws of affinity were replaced by the laws of quantum chemistry and chemical thermodynamics.