Although "the lion's paw" thing has been much quoted note that the details of Newton's solution were not preserved, there's only a single paragraph that was pub

Although "the lion's paw" thing has been much quoted note that the details of Newton's solution were not preserved, there's only a single paragraph that was published by Leibniz that gives a geometric solution. Assuming Newton did indeed followed a geometric argument to arrive at the solution, Bernoulli's approach that morphs the problem into the equivalent one of light traveling through a medium of varying index of refraction is much more original and more brilliant. To see Bernoulli's solution and for some additional interesting information about the problem see http://fredrickey.info/hm/CalcNotes/brachistochrone.pdf http://fredrickey.info/hm/CalcNotes/brachistochrone.pdf.