[As Chief Scientific Adviser to the British Ministry of Defence] We persist in regarding ourselves as a Great Power, capable of everything and only temporarily handicapped by economic difficulties. We are not a great power and never will be again. We are a great nation, but if we continue to behave like a Great Power we shall soon cease to be a great nation. Let us take warning from the fate of the Great Powers of the past and not burst ourselves with pride (see Aesop’s fable of the frog). (1949)

A chemical compound once formed would persist for ever, if no alteration took place in surrounding conditions. But to the student of Life the aspect of nature is reversed. Here, incessant, and, so far as we know, spontaneous change is the rule, rest the exception—the anomaly to be accounted for. Living things have no inertia and tend to no equilibrium.

A fool who, after plain warning, persists in dosing himself with dangerous drugs should be free to do so, for his death is a benefit to the race in general.

For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.

I believe in the not-too-distant future, people are going to learn to trust their information to the Net more than they now do, and be able to essentially manage very large amounts and perhaps their whole lifetime of information in the Net with the notion that they can access it securely and privately for as long as they want, and that it will persist over all the evolution and technical changes.

I was appalled to find that the first referee recommended that part A be omitted and B condensed while the second referee recommended that B should be omitted and A condensed! Perceiving that even referees were not infallible, I decided to persist, and after a lot of bother to myself and to other referees I got both parts published.

Professor Sylvester’s first high class at the new university Johns Hopkins consisted of only one student, G. B. Halsted, who had persisted in urging Sylvester to lecture on the modem algebra. The attempt to lecture on this subject led him into new investigations in quantics.

Some things mankind can finish and be done with, but not ... science, that persists, and changes from ancient Chaldeans studying the stars to a new telescope with a 200-inch reflector and beyond; not religion, that persists, and changes from old credulities and world views to new thoughts of God and larger apprehensions of his meaning.

The cell was the first invention of the animal kingdom, and all higher animals are and must be cellular in structure. Our tissues were formed ages on ages ago; they have all persisted. Most of our organs are as old as worms. All these are very old, older than the mountains.

The scientific method is a potentiation of common sense, exercised with a specially firm determination not to persist in error if any exertion of hand or mind can deliver us from it. Like other exploratory processes, it can be resolved into a dialogue between fact and fancy, the actual and the possible; between what could be true and what is in fact the case. The purpose of scientific enquiry is not to compile an inventory of factual information, nor to build up a totalitarian world picture of Natural Laws in which every event that is not compulsory is forbidden. We should think of it rather as a logically articulated structure of justifiable beliefs about nature. It begins as a story about a Possible World—a story which we invent and criticise and modify as we go along, so that it ends by being, as nearly as we can make it, a story about real life.

There are many examples of old, incorrect theories that stubbornly persisted, sustained only by the prestige of foolish but well-connected scientists. ... Many of these theories have been killed off only when some decisive experiment exposed their incorrectness.

There is no failure for the man who realizes his power, who never knows when he is beaten; there is no failure for the determined endeavor; the unconquerable will. There is no failure for the man who gets up every time he falls, who rebounds like a rubber ball, who persist when everyone else gives up, who pushes on when everyone else turns back.

Wallace’s error on human intellect arose from the in adequacy of his rigid selectionism, not from a failure to apply it. And his argument repays our study today, since its flaw persists as the weak link in many of the most ‘modern’ evolutionary speculations of our current literature. For Wallace’s rigid selectionism is much closer than Darwin’s pluralism to the attitude embodied in our favored theory today, which, ironically in this context, goes by the name of ‘Neo-Darwinism.’