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“I don’t know what the fuss is all about—Dirac did it all before me.” — Richard Feynman (c.1970), recollected by Freeman Dyson (2005) “In mathematical theories the question of notation, while not of primary importance, is yet worthy of careful consideration, since a good notation can be of great value in helping the development of a theory, by making it easy to write down those quantities or combinations of quantities that are important, and difficult or impossible to write down those that are unimportant….”. P. A. M. Dirac (1939) [1] “ Mathematics is the tool specially suited for dealing with abstract concepts of any kind…”. P. A. M. Dirac, “ The principles of Quantum Mechanics” (Oxford, 1930) [2].