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- Motivation for Napier's Logarithms 2 answers
I just read that logarithms were not initially defined in terms of their inverse relationship to exponential functions (and that Euler was the first to develop them in this way).
So how were they initially defined? All I could find on an (admittedly cursory) internet search was that logarithms were used to streamline multiplication and division, and also the calculation of "sines", for which extensive tables were constructed. Does anyone know how these tables were made?
And is there a reason that the etymology of "logarithm" seems to be "ratio-number"? From dictionary.com:
1610s, Mod.L. logarithmus, coined by Scot. mathematician John Napier (1550-1617), lit. "ratio-number," from Gk. logos "proportion, ratio, word" (see logos) + arithmos "number" (see arithmetic). Related: Logarithmic.