“[T]he symbols of algebra, when employed in abstruse and complex theoretical investigations, constitute a sort of thought-saving machine, by whose aid a person skilled in its use can solve problems respecting quantities, and dispense with the mental labour of thinking of the quantities denoted by the symbols, except at the beginning and the end of the operation.”

—  William John Macquorn Rankine

p, 125
"On the Harmony of Theory and Practice in Mechanics" (Jan. 3, 1856)

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William John Macquorn Rankine28
civil engineer 1820–1872

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