... in time of war, soldiers, however sensible, care a great deal more on some occasions about slaking their thirst than about the danger of enteric fever.
[Better known as typhoid, the disease is often spread by drinking contaminated water.]

... we ought to have saints' days to commemorate the great discoveries which have been made for all mankind, and perhaps for all time—or for whatever time may be left to us. Nature ... is a prodigal of pain. I should like to find a day when we can take a holiday, a day of jubilation when we can fête good Saint Anaesthesia and chaste and pure Saint Antiseptic. ... I should be bound to celebrate, among others, Saint Penicillin...

[Should Britain fail, then the entire world would] sink into the abyss of a new dark age made more sinister ... by the lights of perverted science.

Air Chief Marshal Harris [objecting to a change in strategy recommended by statisticians]: Are we fighting this war with weapons or the slide rule?
Churchill [after puffing on his cigar]: That's a good idea. Let's try the slide rule.

A study of Disease—of Pestilences methodically prepared and deliberately launched upon man and beast—is certainly being pursued in the laboratories of more than one great country. Blight to destroy crops, Anthrax to slay horses and cattle, Plague to poison not armies but whole districts—such are the lines along which military science is remorselessly advancing.

An extra yawn one morning in the springtime, an extra snooze one night in the autumn is all that we ask in return for dazzling gifts. We borrow an hour one night in April; we pay it back with golden interest five months later.

Broadly speaking, the short words are the best, and the old words are the best of all.

By God’s mercy British and American science outpaced all German efforts. … This revelation of the secrets of nature, long mercifully withheld from man, should arouse the most solemn reflections in the mind and conscience of every human being capable of comprehension. We must indeed pray that these awful agencies will be made to conduce to peace among the nations, and that instead of wreaking measureless havoc upon the entire globe, may become a perennial fountain of world prosperity.
[Concerning use of the atomic bomb.]

Food is at present obtained almost entirely from the energy of the sunlight. The radiation from the sun produces from the carbonic acid in the air more or less complicated carbon compounds which serve us in plants and vegetables. We use the latent chemical energy of these to keep our bodies warm, we convert it into muscular effort. We employ it in the complicated process of digestion to repair and replace the wasted cells of our bodies. … If the gigantic sources of power become available, food would be produced without recourse to sunlight. Vast cellars, in which artificial radiation is generated, may replace the cornfields and potato patches of the world.

I am always willing to learn, however I do not always like to be taught.

I had a feeling once about Mathematics—that I saw it all. Depth beyond depth was revealed to me—the Byss and Abyss. I saw—as one might see the transit of Venus or even the Lord Mayor’s Show—a quantity passing through infinity and changing its sign from plus to minus. I saw exactly why it happened and why the tergiversation was inevitable but it was after dinner and I let it go.

I have always considered that the substitution of the internal combustion engine for the horse marked a very gloomy milestone in the progress of mankind.

I pass with relief from the tossing sea of Cause and Theory to the firm ground of Result and Fact.

Immense deposits of kimmeridge clay, containing the oil-bearing bands or seams, stretch across England from Dorsetshire to Lincolnshire. [An early political recognition of the native resource. The Geological Survey had identified the inflammable oil shale in reports since at least 1888.]

It is a good thing from an uneducated man to read books of quotations.

It is a very strange thing to reflect that but for the invention of Professor Haber the Germans could not have continued the War after their original stack of nitrates was exhausted. The invention of this single man has enabled them, utilising the interval in which their accumulations were used up, not only to maintain an almost unlimited supply of explosives for all purposes, but to provide amply for the needs of agriculture in chemical manures. It is a remarkable fact, and shows on what obscure and accidental incidents the fortunes of possible the whole world may turn in these days of scientific discovery.
[During World War I, Fritz Haber and Karl Bosch invented a large scale process to cause the direct combination of hydrogen and nitrogen gases to chemically synthesize ammonia, thus providing a replacement for sodium nitrate in the manufacture of explosives and fertilizers.]

It is arguable whether the human race have been gainers by the march of science beyond the steam engine. Electricity opens a field of infinite conveniences to ever greater numbers, but they may well have to pay dearly for them. But anyhow in my thought I stop short of the internal combustion engine which has made the world so much smaller. Still more must we fear the consequences of entrusting a human race so little different from their predecessors of the so-called barbarous ages such awful agencies as the atomic bomb. Give me the horse.

It may be that ... when the advance of destructive weapons enables everyone to kill everybody else nobody will want to kill anyone at all. [Referring to the hydrogen bomb.]

May there not be methods of using explosive energy incomparably more intense than anything heretofore discovered? Might not a bomb no bigger than an orange be found to possess a secret power to destroy a whole block of buildings—nay, to concentrate the force of a thousand tons of cordite and blast a township at a stroke? Could not explosives even of the existing type be guided automatically in flying machines by wireless or other rays, without a human pilot, in ceaseless procession upon a hostile city, arsenal, camp or dockyard?

New sources of power … will surely be discovered. Nuclear energy is incomparably greater than the molecular energy we use today. The coal a man can get in a day can easily do five hundred times as much work as himself. Nuclear energy is at least one million times more powerful still. If the hydrogen atoms in a pound of water could be prevailed upon to combine and form helium, they would suffice to drive a thousand-horsepower engine for a whole year. If the electrons, those tiny planets of the atomic systems, were induced to combine with the nuclei in hydrogen, the horsepower would be 120 times greater still. There is no question among scientists that this gigantic source of energy exists. What is lacking is the match to set the bonfire alight, or it may be the detonator to cause the dynamite to explode. The scientists are looking for this.
[In his last major speech to the House of Commons on 1 Mar 1955, Churchill quoted from his original printed article, nearly 25 years earlier.]

Occasionally he stumbled over the truth but he always picked himself up and hurried on as if nothing had happened.

On 17th July there came to us at Potsdam the eagerly-awaited news of the trial of the atomic bomb in the [New] Mexican desert. Success beyond all dreams crowded this sombre, magnificent venture of our American allies. The detailed reports ... could leave no doubt in the minds of the very few who were informed, that we were in the presence of a new factor in human affairs, and possessed of powers which were irresistible.

Praise up the humanities, my boy. That will make them think that you are broad-minded.

Science bestowed immense new powers on man, and, at the same time, created conditions which were largely beyond his comprehension.

Science burrows its insulted head in the filth of slaughterous inventions.

Science unfolded her treasures and her secrets to the desperate demands of men, and placed in their hands agencies and apparatus almost decisive in their character.
Reflecting on the outcome of World War I, and an ominous future.

Science, which now offers us a golden age with one hand, offers at the same time with the other the doom of all that we have built up inch by inch since the Stone Age and the dawn of any human annals. My faith is in the high progressive destiny of man. I do not believe we are to be flung back into abysmal darkness by those fiercesome discoveries which human genius has made. Let us make sure that they are servants, but not our masters.

Scientists should be on tap, but not on top.

Some of my cousins who had the great advantage of University education used to tease me with arguments to prove that nothing has any existence except what we think of it. … These amusing mental acrobatics are all right to play with. They are perfectly harmless and perfectly useless. ... I always rested on the following argument. … We look up to the sky and see the sun. Our eyes are dazzled and our senses record the fact. So here is this great sun standing apparently on no better foundation than our physical senses. But happily there is a method, apart altogether from our physical senses, of testing the reality of the sun. It is by mathematics. By means of prolonged processes of mathematics, entirely separate from the senses, astronomers are able to calculate when an eclipse will occur. They predict by pure reason that a black spot will pass across the sun on a certain day. You go and look, and your sense of sight immediately tells you that their calculations are vindicated. So here you have the evidence of the senses reinforced by the entirely separate evidence of a vast independent process of mathematical reasoning. We have taken what is called in military map-making “a cross bearing.” When my metaphysical friends tell me that the data on which the astronomers made their calculations, were necessarily obtained originally through the evidence of the senses, I say, “no.” They might, in theory at any rate, be obtained by automatic calculating-machines set in motion by the light falling upon them without admixture of the human senses at any stage. When it is persisted that we should have to be told about the calculations and use our ears for that purpose, I reply that the mathematical process has a reality and virtue in itself, and that onie discovered it constitutes a new and independent factor. I am also at this point accustomed to reaffirm with emphasis my conviction that the sun is real, and also that it is hot— in fact hot as Hell, and that if the metaphysicians doubt it they should go there and see.

The Dark Ages may return—the Stone Age may return on the gleaming wings of Science; and what might now shower immeasureable material blessings upon mankind may even bring about its total destruction. Beware! I say. Time may be short.
Referring to the discovery of atomic energy.

The empires of the future are the empires of the mind.

The latest refinements of science are linked with the cruelties of the Stone Age.

The longer you can look back, the farther you can look forward.

The point [is] largely scientific in character …[concerning] the methods which can be invented or adopted or discovered to enable the Earth to control the Air, to enable defence from the ground to exercise control—indeed dominance—upon aeroplanes high above its surface. … science is always able to provide something. We were told that it was impossible to grapple with submarines, but methods were found … Many things were adopted in war which we were told were technically impossible, but patience, perseverance, and above all the spur of necessity under war conditions, made men’s brains act with greater vigour, and science responded to the demands.
[Remarks made in the House of Commons on 7 June 1935. His speculation was later proved correct with the subsequent development of radar during World War II, which was vital in the air defence of Britain.]

The state must increasingly and earnestly concern itself with the care of the sick and the aged, and above all, the children. … I look forward to the universal establishment of minimum standards of life and labor. … I do not want to see impaired the vigour of competition, but we can do much to mitigate the consequences of failure. We can draw a line below which we will not allow persons to live and labour yet above which they may compete with all the strength of their manhood. We want to have free competition upwards; we decline to allow free competition to run downwards. … We do not want to pull down the structure of science and civilization — but to spread a net over the abyss.

The world, nature, human beings, do not move like machines. The edges are never clear-cut, but always frayed. Nature never draws a line without smudging it.

There are two processes which we adopt consciously or unconsciously when we try to prophesy. We can seek a period in the past whose conditions resemble as closely as possible those of our day, and presume that the sequel to that period will, save for some minor alterations, be similar. Secondly, we can survey the general course of development in our immediate past, and endeavor to prolong it into the near future. The first is the method the historian; the second that of the scientist. Only the second is open to us now, and this only in a partial sphere.

This is a strange Christmas Eve. Almost the whole world is locked in deadly struggle, and, with the most terrible weapons which science can devise, the nations advance upon each other. Ill would it be for us this Christmastide if we were not sure that no greed for the land or wealth of any other people, no vulgar ambition, no morbid lust for material gain at the expense of others, had led us to the field. Here, in the midst of war, raging and roaring over all the lands and seas, creeping nearer to our hearts and homes, here, amid all the tumult, we have tonight the peace of the spirit in each cottage home and in every generous heart. Therefore we may cast aside for this night at least the cares and dangers which beset us, and make for the children an evening of happiness in a world of storm. Here, then, for one night only, each home throughout the English-speaking world should be a brightly-lighted island of happiness and peace.
Let the children have their night of fun and laughter. Let the gifts of Father Christmas delight their play. Let us grown-ups share to the full in their unstinted pleasures before we turn again to the stern task and the formidable years that lie before us, resolved that, by our sacrifice and daring, these same children shall not be robbed of their inheritance or denied their right to live in a free and decent world.

Victory [in war] is the beautiful, bright-coloured flower. Transport is the stem without which it could never have blossomed. (1899)

We are all worms. But I do believe that I am a glow-worm.

We know enough to be sure that the scientific achievements of the next fifty years will be far greater, more rapid, and more surprising, than those we have already experienced. … Wireless telephones and television, following naturally upon the their present path of development, would enable their owner to connect up to any room similarly equipped and hear and take part in the conversation as well as if he put his head in through the window.

We used to be a source of fuel; we are increasingly becoming a sink. These supplies of foreign liquid fuel are no doubt vital to our industry, but our ever-increasing dependence upon them ought to arouse serious and timely reflection. The scientific utilisation, by liquefaction, pulverisation and other processes, or our vast and magnificent deposits of coal, constitutes a national object of prime importance.

When we look back beyond one hundred years over the long trails of history, we see immediately why the age we live in differs from all other ages in human annals. … It remained stationary in India and in China for thousands of years. But now it is moving very fast. … A priest from Thebes would probably have felt more at home at the council of Trent, two thousand years after Thebes had vanished, than Sir Isaac Newton at a modern undergraduate physical society, or George Stephenson in the Institute of Electrical Engineers. The changes have have been so sudden and so gigantic, that no period in history can be compared with the last century. The past no longer enables us even dimly to measure the future.

With a greater knowledge of what are called hormones, i.e., the chemical messengers in our blood, it will be possible to control growth. We shall escape the absurdity of growing a whole chicken in order to eat the breast or wing, by growing these parts separately under a suitable medium.

You are wrong all along the line—wrong in your logic, wrong in your statecraft, wrong in your arithmetic, wrong even in your demagogy—right only in having at last the candour and courage to avow your true opinions.

You cannot ask us to take sides against arithmetic.

I might paraphrase Churchill and say: never have I received so much for so little.
[Exemplifying humility, upon accepting the Nobel Prize in Chemistry.]

He [Winston Churchill] is rather like a layer cake. One layer was certainly seventeenth century. The eighteenth century in him is obvious. There was the nineteenth century, and a large slice, of course, of the twentieth century; and another, curious, layer which may possibly have been the twenty-first.