Truth is like a vast tree which yields more and more fruit the more you nurture it. The deeper the search in the mind of truth, the richer the discovery of the gems buried there.
However we select from nature a complex [of phenomena] using the criterion of simplicity, in no case will its theoretical treatment turn out to be forever appropriate (sufficient).... I do not doubt that the day will come when [general relativity], too, will have to yield to another one, for reasons which at present we do not yet surmise. I believe that this process of deepening theory has no limits.
But the most brilliant propagandist technique will yield no success unless one fundamental principle is borne in mind constantly and with unflagging attention. It must confine itself to a few points and repeat them over and over. Here, as so often in this world, persistence is the first and most important requirement for success.
A great country needs more people to serve it. A small country needs more people to serve. So, if both shall get what they need, the great country ought to yield.
Let no young man choosing the law for a calling for a moment yield to the popular belief -- resolve to be honest at all events; and if in your own judgment you cannot be an honest lawyer, resolve to be honest without being a lawyer.