Luck is what happens when preparation meets opportunity. Replace luck with success, and for work in R&D I strongly agree with this piece of wisdom. It is (disputedly) attributed to Seneca the Younger (L. Annaeus Seneca, 4 BC – AD 65).
I always worked on the assumption that if I do not remember an equation https://putty-ssh.com , I will never recognize the need to use it, when the opportunity comes along. And – bingo – on that lucky day I was lucky enough to be able to design a product based on Eytelwein’s Equation (the Capstan Equation). I did remember, even though I am not sure if it was just because the name is so unusual, sorry Dr. Eytelwein. The product was a success.
The opposing opinion of course is that it is sufficient to know where you can find certain knowledge (today always on the web) and that to remember equations is unnecessary ballast.
But then I think to be able to apply an equation – when the opportunity comes – we should have an idea about its structure. In the Capstan Equation the important thing to know is that the force increases exponentially with the wrap angle and with the coefficient of friction, and that the diameter of the capstan has no influence. If you don’t know this, you will not be able to apply the capstan principle.
What Seneca wrote in book 7 of “De Beneficiis” is:
“The best wrestler,” he ( the cynic Demetrius) would say, “is not he who has learned thoroughly all the tricks and twists of the art, which are seldom met with in actual wrestling, but he who has well and carefully trained himself in one or two of them, and watches keenly for an opportunity for practicing them.”
Magnus luctator est, non qui omnes numeros nexusque perdidicit, quorum usus sub adversario rarus est, sed qui in uno se aut altero bene ac diligenter exercuit et eorum occasiones intentus expectat.
Well, in R&D to know a couple of tricks (or equations) is certainly not enough. The real question to me seems to be about the optimum number of “tricks” to know.