[In treating the sick], the first thing to consider is the provision of fresh air, clean water, and a healthy diet.

[Mercurial medicines] affect the human constitution in a peculiar manner, taking, so to speak, an iron grasp of all its systems, and penetrating even to the bones, by which they not only change the healthy action of its vessels, and general structure, but greatly impair and destroy its energies; so that their abuse is rarely overcome. When the tone of the stomach, intestines, or nervous system generally, has been once injured by this mineral ... it could seldom be restored.

[You are] A healthy man out of health.

[When questioned on his longevity] First of all, I selected my ancestors very wisely. ... They were long-lived, healthy people. Then, as a chemist, I know how to eat, how to exercise, keep my blood circulating. ... I don't worry. I don't get angry at people. I don't worry about things I can't help. I do what I can to make the world a better place to live, but I don't complain if things aren't right. As a scientist I take the world as I find it.
[About celebrating his 77th birthday by swimming a half mile in 22 minutes] I used swim fins and webbed gloves because a man of intelligence should apply his power efficiently, not just churn the water.

He who doth with the greatest exactness imaginable, weigh every individual thing that shall or hath hapned to his Patient, and may be known from the Observations of his own, or of others, and who afterwards compareth all these with one another, and puts them in an opposite view to such Things as happen in a healthy State; and lastly, from all this with the nicest and severest bridle upon his reasoning faculty riseth to the knowledge of the very first Cause of the Disease, and of the Remedies fit to remove them; He, and only He deserveth the Name of a true Physician.

A drop of old tuberculin, which is an extract of tubercle bacilli, is put on the skin and then a small superficial scarification is made by turning, with some pressure, a vaccination lancet on the surface of the skin. The next day only those individuals show an inflammatory reaction at the point of vaccination who have already been infected with tuberculosis, whereas the healthy individuals show no reaction at all. Every time we find a positive reaction, we can say with certainty that the child is tuberculous.

A healthy body is a guest-chamber for the soul; a sick body is a prison.

A science calling itself “psychology” and professing to be a science of the human mind (not merely the sick mind), ought to form its estimate of human beings by taking into account healthy minds as well as sick ones.

A sick man talks obsessively about his illness; a healthy man never talks about his health; for as Pirandello points out, we take happiness for granted, and only begin to question life when we are unhappy.

Abraham Maslow, felt … [an] instinctive revolt against the “atmosphere” of Freudian psychology, with its emphasis on sickness and neurosis, and decided that he might obtain some equally interesting results if he studied extremely healthy people.

All that we can do, is to keep steadily in mind that each organic being is striving to increase at a geometrical ratio; that each at some period of its life, during some season of the year, during each generation or at intervals, has to struggle for life, and to suffer great destruction. When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.

An extremely healthy dose of skepticism about the reliability of science is an absolutely inevitable consequence of any scientific study of its track record.

And men ought to know that from nothing else but thence [from the brain] come joys, delights, laughter and sports, and sorrows, griefs, despondency, and lamentations. And by this, in an especial manner, we acquire wisdom and knowledge, and see and hear, and know what are foul and hat are fair, what are bad and what are good, what are sweet, and what unsavory... And by the same organ we become mad and delirious, and fears and terrors assail us... All these things we endure from the brain, when it is not healthy... In these ways I am of the opinion that the brain exercises the greatest power in the man. This is the interpreter to us of those things which emanate from the air, when it [the brain] happens to be in a sound state.

Early to bed and early to rise, makes a man healthy wealthy and wise.

Feeling weightless… it’s so many things together. A feeling of pride, of healthy solitude, of dignified freedom from everything that’s dirty, sticky. You feel exquisitely comfortable . . . and you feel you have so much energy, such an urge to do things, such an ability to do things. And you work well, yes, you think well, without sweat, without difficulty as if the biblical curse in the sweat of thy face and in sorrow no longer exists, As if you’ve been born again.

For the first time in our national history the higher-education enterprise that we pass on to our children and grandchildren will be less healthy, less able to respond to national needs … than the enterprise that we ourselves inherited.

For this knowledge of right living, we have sought a new name... . As theology is the science of religious life, and biology the science of [physical] life ... so let Oekology be henceforth the science of [our] normal lives ... the worthiest of all the applied sciences which teaches the principles on which to found... healthy... and happy life.

For what is that which we call evil but the absence of good? In the bodies of animals, disease and wounds mean nothing but the absence of health; for when a cure is effected, that does not mean that the evils which were present—namely, the diseases and wounds—go away from the body and dwell elsewhere: they altogether cease to exist; for the wound or disease is not a substance, but a defect in the fleshly substance,—the flesh itself being a substance, and therefore something good, of which those evils—that is, privations of the good which we call health—are accidents. Just in the same way, what are called vices in the soul are nothing but privations of natural good. And when they are cured, they are not transferred elsewhere: when they cease to exist in the healthy soul, they cannot exist anywhere else.

Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select—doctor, lawyer, artist, merchant-chief and, yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors. (1930)

Given one has before oneself a strong, healthy, youth rich in spirited blood and a powerless, weak, cachectic old man scarcely capable of breathing. If now the physician wishes to practise the rejuvenating art on the latter, he should make silver tubes which fit into each other: open then the artery of the healthy person and introduce one of the tubes into it and fasten it into the artery; thereupon he opens also the artery of the ill person...
[First detailed description of blood transfusion (1615)]

However, on many occasions, I examined normal blood and normal tissues and there was no possibility of overlooking bacteria or confusing them with granular masses of equal size. I never found organisms. Thus, I conclude that bacteria do not occur in healthy human or animal tissues.

I believe citizens are beginning to realize that their birthright, a healthy ecosystem, has been stolen, and they want it back.

I don't really care how time is reckoned so long as there is some agreement about it, but I object to being told that I am saving daylight when my reason tells me that I am doing nothing of the kind. I even object to the implication that I am wasting something valuable if I stay in bed after the sun has risen. As an admirer of moonlight I resent the bossy insistence of those who want to reduce my time for enjoying it. At the back of the Daylight Saving scheme I detect the bony, blue-fingered hand of Puritanism, eager to push people into bed earlier, and get them up earlier, to make them healthy, wealthy and wise in spite of themselves.

I have divers times examined the same matter (human semen) from a healthy man... not from a sick man... nor spoiled by keeping... for a long time and not liquefied after the lapse of some time... but immediately after ejaculation before six beats of the pulse had intervened; and I have seen so great a number of living animalcules... in it, that sometimes more than a thousand were moving about in an amount of material the size of a grain of sand... I saw this vast number of animalcules not all through the semen, but only in the liquid matter adhering to the thicker part.

I have never yet met a healthy person who worried very much about his health, or a really good person who worried much about his own soul.

I have patiently born with abundance of Clamour and Ralary [raillery], for beginning a new Practice here (for the Good of the Publick) which comes well Recommended, from Gentlemen of Figure & Learning, and which well agrees to Reason, when try’d & duly considered, viz. Artificially giving the Small Pocks, by Inoculation, to One of my Children, and Two of my Slaves, in order to prevent the hazard of Life… . and they never took one grain or drop of Medicine since, & are perfectly well.

I have recently observed and stated that the serum of normal people is capable of clumping the red cells of other healthy individuals... As commonly expressed, it can be said that in these cases at least two different kinds of agglutinins exist, one kind in A, the other in B, both together in C. The cells are naturally insensitive to the agglutinins in their own serum.

I was suffering from a sharp attack of intermittent fever, and every day during the cold and succeeding hot fits had to lie down for several hours, during which time I had nothing to do but to think over any subjects then particularly interesting me. One day something brought to my recollection Malthus's 'Principles of Population', which I had read about twelve years before. I thought of his clear exposition of 'the positive checks to increase'—disease, accidents, war, and famine—which keep down the population of savage races to so much lower an average than that of more civilized peoples. It then occurred to me that these causes or their equivalents are continually acting in the case of animals also; and as animals usually breed much more rapidly than does mankind, the destruction every year from these causes must be enormous in order to keep down the numbers of each species, since they evidently do not increase regularly from year to year, as otherwise the world would long ago have been densely crowded with those that breed most quickly. Vaguely thinking over the enormous and constant destruction which this implied, it occurred to me to ask the question, Why do some die and some live? The answer was clearly, that on the whole the best fitted live. From the effects of disease the most healthy escaped; from enemies, the strongest, swiftest, or the most cunning; from famine, the best hunters or those with the best digestion; and so on. Then it suddenly flashed upon me that this self-acting process would necessarily improve the race, because in every generation the inferior would inevitably be killed off and the superior would remain—that is, the fittest would survive.
[The phrase 'survival of the fittest,' suggested by the writings of Thomas Robert Malthus, was expressed in those words by Herbert Spencer in 1865. Wallace saw the term in correspondence from Charles Darwin the following year, 1866. However, Wallace did not publish anything on his use of the expression until very much later, and his recollection is likely flawed.]

I’m sick of people thinking that efficiency is going to be sufficient. I’m sick of seeing people say, “I’m going to reduce my carbon footprint,” and think that being less bad is being good. … I want healthy, safe things in closed cycles, not just being less bad.

If you confine yourself to this Skinnerian technique, you study nothing but the learning apparatus and you leave out everything that is different in octopi, crustaceans, insects and vertebrates. In other words, you leave out everything that makes a pigeon a pigeon, a rat a rat, a man a man, and, above all, a healthy man healthy and a sick man sick.

In acute diseases the physician must conduct his inquiries in the following way. First he must examine the face of the patient, and see whether it is like the faces of healthy people, and especially whether it is like its usual self. Such likeness will be the best sign, and the greatest unlikeness will be the most dangerous sign. The latter will be as follows. Nose sharp, eyes hollow, temples sunken, ears cold and contracted with their lobes turned outwards, the skin about the face hard and tense and parched, the colour of the face as a whole being yellow or black.

In the same sense that our judicial system presumes us to be innocent until proven guilty, a medical care system may work best if it starts with the presumption that most people are healthy. Left to themselves, computers may try to do it in the opposite way, taking it as given that some sort of direct, continual, professional intervention is required all the time, in order to maintain the health of each citizen, and we will end up spending all our money on nothing but this.

Indeed, the ideal for a well-functioning democratic state is like the ideal for a gentleman’s well-cut suit—it is not noticed. For the common people of Britain, Gestapo and concentration camps have approximately the same degree of reality as the monster of Loch Ness. Atrocity propaganda is helpless against this healthy lack of imagination.

Logic is the hygiene the mathematician practices to keep his ideas healthy and strong.

Mathematicians create by acts of insight and intuition. Logic then sanctions the conquests of intuition. It is the hygiene that mathematics practices to keep its ideas healthy and strong. Moreover, the whole structure rests fundamentally on uncertain ground, the intuition of humans. Here and there an intuition is scooped out and replaced by a firmly built pillar of thought; however, this pillar is based on some deeper, perhaps less clearly defined, intuition. Though the process of replacing intuitions with precise thoughts does not change the nature of the ground on which mathematics ultimately rests, it does add strength and height to the structure.

Mathematics is a structure providing observers with a framework upon which to base healthy, informed, and intelligent judgment. Data and information are slung about us from all directions, and we are to use them as a basis for informed decisions. … Ability to critically analyze an argument purported to be logical, free of the impact of the loaded meanings of the terms involved, is basic to an informed populace.

Men ought to know that from the brain, and from the brain only, arise our pleasures, joys, laughter and jests, as well as our sorrows, pains, griefs and tears. Through it, in particular, we think, see, hear, and distinguish the ugly from the beautiful, the bad from the good, the pleasant from the unpleasant, in some cases using custom as a test, in others perceiving them from their utility. It is the same thing which makes us mad or delirious, inspires us with dread or fear, whether by night or by day, brings sleeplessness, inopportune mistakes, aimless anxieties, absent-mindedness, and acts that are contrary to habit. These things that we suffer all come from the brain, when it is not healthy, but becomes abnormally hot, cold, moist, or dry, or suffers any other unnatural affection to which it was not accustomed. Madness comes from its moistness.

No matter how we twist and turn we shall always come back to the cell. The eternal merit of Schwann does not lie in his cell theory that has occupied the foreground for so long, and perhaps will soon be given up, but in his description of the development of the various tissues, and in his demonstration that this development (hence all physiological activity) is in the end traceable back to the cell. Now if pathology is nothing but physiology with obstacles, and diseased life nothing but healthy life interfered with by all manner of external and internal influences then pathology too must be referred back to the cell.

No one has ever done this before, … What we are trying to do here is to create a stem cell line without injuring an embryo. Our cells can go on to become a healthy, kicking baby.

No video, no photographs, no verbal descriptions, no lectures can provide the enchantment that a few minutes out-of-doors can: watch a spider construct a web; observe a caterpillar systematically ravaging the edge of a leaf; close your eyes, cup your hands behind your ears, and listen to aspen leaves rustle or a stream muse about its pools and eddies. Nothing can replace plucking a cluster of pine needles and rolling them in your fingers to feel how they’re put together, or discovering that “sedges have edges and grasses are round,” The firsthand, right-and-left-brain experience of being in the out-of-doors involves all the senses including some we’ve forgotten about, like smelling water a mile away. No teacher, no student, can help but sense and absorb the larger ecological rhythms at work here, and the intertwining of intricate, varied and complex strands that characterize a rich, healthy natural world.

Not one idiot in a thousand has been entirely refractory to treatment, not one in a hundred has not been made more happy and healthy; more than thirty per cent have been taught to conform to social and moral law, and rendered capable of order, of good feeling, and of working like the third of a man; more than forty per cent have become capable of the ordinary transactions of life under friendly control, of understanding moral and social abstractions, of working like two-thirds of a man.

Oddly enough, eccentrics are happier and healthier than conformists. A study of 1,000 people found that eccentrics visit a doctor an average of just once every eight years, while conformists go twice a year. Eccentrics apparently enjoy better health because they feel less pressured to follow society’s rules, said the researcher who did the study at Royal Edinburgh Hospital in Scotland.

Our ancestors, when about to build a town or an army post, sacrificed some of the cattle that were wont to feed on the site proposed and examined their livers. If the livers of the first victims were dark-coloured or abnormal, they sacrificed others, to see whether the fault was due to disease or their food. They never began to build defensive works in a place until after they had made many such trials and satisfied themselves that good water and food had made the liver sound and firm. …healthfulness being their chief object.

Our school education ignores, in a thousand ways, the rules of healthy development; and the results … are gained very generally at the cost of physical and mental health.

Over and over again, we must stress that a healthy ecology is the basis for a healthy economy.

Physicists do, of course, show a healthy respect for High Voltage, Radiation, and Liquid Hydrogen signs. They are not reckless. I can think of only six who have been killed on the job.

Rising before daylight is also to be commended; it is a healthy habit, and gives more time for the management of the household as well as for liberal studies.

Science did not germinate and grow on a healthy prairie of ignorance but in a noisome jungle of magic and superstition, which again and again choked the seedlings of knowledge.

Science is intimately integrated with the whole social structure and cultural tradition. They mutually support one other—only in certain types of society can science flourish, and conversely without a continuous and healthy development and application of science such a society cannot function properly.

Scientific knowledge does limit the imagination, but only in the same healthy way that sanity limits what we take as real.

Scientists come in two varieties, hedgehogs and foxes. I borrow this terminology from Isaiah Berlin (1953), who borrowed it from the ancient Greek poet Archilochus. Archilochus told us that foxes know many tricks, hedgehogs only one. Foxes are broad, hedgehogs are deep. Foxes are interested in everything and move easily from one problem to another. Hedgehogs are only interested in a few problems that they consider fundamental, and stick with the same problems for years or decades. Most of the great discoveries are made by hedgehogs, most of the little discoveries by foxes. Science needs both hedgehogs and foxes for its healthy growth, hedgehogs to dig deep into the nature of things, foxes to explore the complicated details of our marvelous universe. Albert Einstein and Edwin Hubble were hedgehogs. Charley Townes, who invented the laser, and Enrico Fermi, who built the first nuclear reactor in Chicago, were foxes.

Several of the young people here [at the fifth White House Science Fair] are first-generation Americans. Their parents came here, in part, so their kids could develop their talents and make a difference in the world. … America is going to be stronger and smarter and healthier, and a much more interesting place because of you.

The degree 48 … in my thermometers holds the middle between between the limit of the most intense cold obtained artificially in a mixture of water, of ice and of sal-ammoniac or even of sea-salt, and the limit of heat which is found in the blood of a healthy man.

The facts obtained in this study may possibly be sufficient proof of the causal relationship, that only the most sceptical can raise the objection that the discovered microorganism is not the cause but only an accompaniment of the disease... It is necessary to obtain a perfect proof to satisfy oneself that the parasite and the disease are ... actually causally related, and that the parasite is the... direct cause of the disease. This can only be done by completely separating the parasite from the diseased organism [and] introducing the isolated parasite into healthy organisms and induce the disease anew with all its characteristic symptoms and properties.

The links between ecosystem and human health are many and obvious: the value in wetlands of filtering pollutants out of groundwater aquifers; the potential future medical use of different plants’ genetic material; the human health effects of heavy metal accumulation in fish and shellfish. It is clear that healthy ecosystems provide the underpinnings for the long-term health of economics and societies.

The rapid growth of industry, the ever increasing population and the imperative need for more varied, wholesome and nourishing foodstuff makes it all the more necessary to exhaust every means at our command to fill the empty dinner pail, enrich our soils, bring greater wealth and influence to our beautiful South land, which is synonymous to a healthy, happy and contented people.

The results of science are never quite true. By a healthy independence of thought perhaps we sometimes avoid adding other people’s errors to our own.

The scientist explores the world of phenomena by successive approximations. He knows that his data are not precise and that his theories must always be tested. It is quite natural that he tends to develop healthy skepticism, suspended judgment, and disciplined imagination.

The simplest way to assure sales is to keep changing the product the market for new things is indefinitely elastic. One of the fundamental purposes of advertising, styling, and research is to foster a healthy dissatisfaction.

The Truly Healthy environment is not merely safe but stimulating.

There are science teachers who actually claim that they teach “a healthy skepticism.” They do not. They teach a profound gullibility, and their dupes, trained not to think for themselves, will swallow any egregious rot, provided it is dressed up with long words and an affectation of objectivity to make it sound scientific.

They hold that the function of universities is to make learning repellent and thus to prevent its becoming dangerously common. And they discharge this beneficent function all the more efficiently because they do it unconsciously and automatically. The professors think they are advancing healthy intellectual assimilation and digestion when they are in reality little better than cancer on the stomach.

This frustration of reading the tabloid press… it would easy to become convinced that the human race is on a mission to divide things into two clean columns… Good or evil, healthy or deadly or natural or chemical… everything organic and natural is good, ignoring the fact that organic natural substances include arsenic… Everything chemical is bad, ignoring that fact the everything is chemicals. Everything is chemicals! The day they discover yoga mats are carcinogenic will be the happiest day of my life.

This is the most exciting part of being human. It is using our brains in the highest way. Otherwise we are just healthy animals.

We are led to think of diseases as isolated disturbances in a healthy body, not as the phases of certain periods of bodily development.

We may, I think, draw a yet higher and deeper teaching from the phenomena of degeneration. We seem to learn from it the absolute necessity of labour and effort, of struggle and difficulty, of discomfort and pain, as the condition of all progress, whether physical or mental, and that the lower the organism the more need there is of these ever-present stimuli, not only to effect progress, but to avoid retrogression. And if so, does not this afford us the nearest attainable solution of the great problem of the origin of evil? What we call evil is the essential condition of progress in the lower stages of the development of conscious organisms, and will only cease when the mind has become so thoroughly healthy, so well balanced, and so highly organised, that the happiness derived from mental activity, moral harmony, and the social affections, will itself be a sufficient stimulus to higher progress and to the attainment of a more perfect life.

We need to think of “blue carbon” and other services provided by healthy marine ecosystems. Mangroves, seagrasses and coastal marshes are great sinks for atmospheric carbon.

We urgently need [the landmark National Ocean Policy] initiative, as we use our oceans heavily: Cargo ships crisscross the sea, carrying goods between continents. Commercial and recreational fishing boats chase fish just offshore. Cruise ships cruise. Oil and gas drilling continues, but hopefully we will add renewable energy projects as well. Without planning, however, these various industrial activities amount to what we call “ocean sprawl,” steamrolling the resources we rely upon for our livelihoods, food, fun, and even the air we breathe. While humankind relies on many of these industries, we also need to keep the natural riches that support them healthy and thriving. As an explorer, I know firsthand there are many places in the ocean so full of life that they should be protected.

Whilst you put up a public house at one end of your street and a provident dispensary at the other, how can you expect your people to be healthy?

Wouldst thou enjoy a long Life, a healthy Body, and a vigorous Mind, and be acquainted also with the wonderful Works of God? labour in the first place to bring thy Appetite into Subjection to Reason.