Le paradoxe, c'est de la graine de vérité. Il suffit d'un terrain propice pour que cela germe, fleurisse et fructifie.
The paradox is the seed of truth. This germ just needs a fertile ground to flourish and bear fruit.

A short, broad man of tremendous vitality, the physical type of Hereward, the last of the English, and his brother-in-arms, Winter, Sylvester’s capacious head was ever lost in the highest cloud-lands of pure mathematics. Often in the dead of night he would get his favorite pupil, that he might communicate the very last product of his creative thought. Everything he saw suggested to him something new in the higher algebra. This transmutation of everything into new mathematics was a revelation to those who knew him intimately. They began to do it themselves. His ease and fertility of invention proved a constant encouragement, while his contempt for provincial stupidities, such as the American hieroglyphics for π and e, which have even found their way into Webster’s Dictionary, made each young worker apply to himself the strictest tests.

A single tree by itself is dependent upon all the adverse chances of shifting circumstances. The wind stunts it: the variations in temperature check its foliage: the rains denude its soil: its leaves are blown away and are lost for the purpose of fertilisation. You may obtain individual specimens of line trees either in exceptional circumstances, or where human cultivation had intervened. But in nature the normal way in which trees flourish is by their association in a forest. Each tree may lose something of its individual perfection of growth, but they mutually assist each other in preserving the conditions of survival. The soil is preserved and shaded; and the microbes necessary for its fertility are neither scorched, nor frozen, nor washed away. A forest is the triumph of the organisation of mutually dependent species.

As agonizing a disease as cancer is, I do not think it can be said that our civilization is threatened by it. … But a very plausible case can be made that our civilization is fundamentally threatened by the lack of adequate fertility control. Exponential increases of population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized.

As each bit of information is added to the sum of human knowledge it is evident that it is the little things that count; that give all the fertility and character; that give all the hope and happiness to human affairs. The concept of bigness is apt to be a delusion, and standardizing processes must not supplant creative impulses.

Ask a follower of Bacon what [science] the new philosophy, as it was called in the time of Charles the Second, has effected for mankind, and his answer is ready; “It has lengthened life; it has mitigated pain; it has extinguished diseases; it has increased the fertility of the soil; it has given new securities to the mariner; it has furnished new arms to the warrior; it has spanned great rivers and estuaries with bridges of form unknown to our fathers; it has guided the thunderbolt innocuously from heaven to earth; it has lighted up the night with the splendour of the day; it has extended the range of the human vision; it has multiplied the power of the human muscles; it has accelerated motion; it has annihilated distance; it has facilitated intercourse, correspondence, all friendly offices, all dispatch of business; it has enabled man to descend to the depths of the sea, to soar into the air, to penetrate securely into the noxious recesses of the earth, to traverse the land in cars which whirl along without horses, to cross the ocean in ships which run ten knots an hour against the wind. These are but a part of its fruits, and of its first-fruits; for it is a philosophy which never rests, which has never attained, which is never perfect. Its law is progress. A point which yesterday was invisible is its goal to-day, and will be its starting-point to-morrow.”

But the Presidence of that mighty Power … its particular Agency and Concern therein: and its Purpose and Design … will more evidently appear, when I shall have proved … That the said Earth, though not indifferently and alike fertil in all parts of it, was yet generally much more fertil than ours is … That its Soil was more luxuriant, and teemed forth its Productions in far greater plenty and abundance than the present Earth does … That when Man was fallen, and had abandoned his primitive Innocence, the Case was much altered: and a far different Scene of Things presented; that generous Vertue, masculine Bravery, and prudent Circumspection which he was before Master of, now deserting him … and a strange imbecility immediately seized and laid hold of him: he became pusillanimous, and was easily ruffled with every little Passion within: supine, and as openly exposed to any Temptation or Assault from without. And now these exuberant Productions of the Earth became a continued Decoy and Snare unto him.

If in a given community unchecked popular rule means unlimited waste and destruction of the natural resources—soil, fertility, waterpower, forests, game, wild-life generally—which by right belong as much to subsequent generations as to the present generation, then it is sure proof that the present generation is not yet really fit for self-control, that it is not yet really fit to exercise the high and responsible privilege of a rule which shall be both by the people and for the people. The term “for the people” must always include the people unborn as well as the people now alive, or the democratic ideal is not realized.

If we and the rest of the backboned animals were to disappear overnight, the rest of the world would get on pretty well. But if [the invertebrates] were to disappear, the world’s ecosystems would collapse. disappear, the land’s ecosystems would collapse. The soil would lose its fertility. Many of the plants would no longer be pollinated. Lots of animals, amphibians, reptiles, birds, mammals would have nothing to eat. And our fields and pastures would be covered with dung and carrion.

In a French book recently translated by Sir William Moyer of Madras, the author [Joseph Chailley] says: “If India possessed a more fertile soil and were better endowed with mineral wealth, she would still languish in poverty if the natives continued to work with the same apathetic indifference as at present. Slackness is the worst curse of the country. At first sight, everybody seems to be taking an active part in some common toil; as a matter of fact, several persons are looking on at the labour of one. As has been cynically remarked, out of five people who seem to be working, one is doing nothing, one is resting, one is looking on and another is helping the previous three. Everyone endeavours to escape his full toll of toil.”

In general, a fact is worth more than theories in the long run. The theory stimulates, but the fact builds. The former in due time is replaced by one better but the fact remains and becomes fertile.

It may very properly be asked whether the attempt to define distinct species, of a more or less permanent nature, such as we are accustomed to deal with amongst the higher plants and animals, is not altogether illusory amongst such lowly organised forms of life as the bacteria. No biologist nowadays believes in the absolute fixity of species … but there are two circumstances which here render the problem of specificity even more difficult of solution. The bacteriologist is deprived of the test of mutual fertility or sterility, so valuable in determining specific limits amongst organisms in which sexual reproduction prevails. Further, the extreme rapidity with which generation succeeds generation amongst bacteria offers to the forces of variation and natural selection a field for their operation wholly unparalleled amongst higher forms of life.

Mathematics is not a book confined within a cover and bound between brazen clasps, whose contents it needs only patience to ransack; it is not a mine, whose treasures may take long to reduce into possession, but which fill only a limited number of veins and lodes; it is not a soil, whose fertility can be exhausted by the yield of successive harvests; it is not a continent or an ocean, whose area can be mapped out and its contour defined: it is limitless as that space which it finds too narrow for its aspirations; its possibilities are as infinite as the worlds which are forever crowding in and multiplying upon the astronomer’s gaze; it is as incapable of being restricted within assigned boundaries or being reduced to definitions of permanent validity, as the consciousness of life, which seems to slumber in each monad, in every atom of matter, in each leaf and bud cell, and is forever ready to burst forth into new forms of vegetable and animal existence.

Most discussions of the population crisis lead logically to zero population growth as the ultimate goal, because any growth rate, if continued, will eventually use up the earth... Turning to the actual measures taken we see that the very use of family planning as the means for implementing population policy poses serious but unacknowledged limits the intended reduction in fertility. The family-planning movement, clearly devoted to the improvement and dissemination of contraceptive devices, states again and again that its purpose is that of enabling couples to have the number of children they want.
With the publication of this article 'zero population growth' and the acronym 'ZPG' came into general use.

One is constantly reminded of the infinite lavishness and fertility of Nature—inexhaustible abundance amid what seems enormous waste. And yet when we look into any of her operations that lie within reach of our minds, we learn that no particle of her material is wasted or worn out. It is eternally flowing from use to use, beauty to yet higher beauty; and we soon cease to lament waste and death, and rather rejoice and exult in the imperishable, unspendable wealth of the universe.

The anxious precision of modern mathematics is necessary for accuracy, … it is necessary for research. It makes for clearness of thought and for fertility in trying new combinations of ideas. When the initial statements are vague and slipshod, at every subsequent stage of thought, common sense has to step in to limit applications and to explain meanings. Now in creative thought common sense is a bad master. Its sole criterion for judgment is that the new ideas shall look like the old ones, in other words it can only act by suppressing originality.

The virgin fertility of our soils, and the vast amount of unskilled labor, have been more of a curse than a blessing to agriculture. This exhaustive system for cultivation, the destruction of forests, the rapid and almost constant decomposition of organic matter, together with the problems of nitrification and denitrification, the multitudinous insects and fungus diseases which are ever increasing with marvelous rapidity year by year, make our agricultural problem one requiring more brains than of the North, East or West.

The vulgar opinion, then, which, on health reasons, condemns vegetable food and so much praises animal food, being so ill-founded, I have always thought it well to oppose myself to it, moved both by experience and by that refined knowledge of natural things which some study and conversation with great men have given me. And perceiving now that such my constancy has been honoured by some learned and wise physicians with their authoritative adhesion (della autorevole sequela), I have thought it my duty publicly to diffuse the reasons of the Pythagorean diet, regarded as useful in medicine, and, at the same time, as full of innocence, of temperance, and of health. And it is none the less accompanied with a certain delicate pleasure, and also with a refined and splendid luxury (non è privo nemmeno d’una certa delicate voluttà e d’un lusso gentile e splendido ancora), if care and skill be applied in selection and proper supply of the best vegetable food, to which the fertility and the natural character of our beautiful country seem to invite us. For my part I have been so much the more induced to take up this subject, because I have persuaded myself that I might be of service to intending diet-reformers, there not being, to my knowledge, any book of which this is the sole subject, and which undertakes exactly to explain the origin and the reasons of it.

There is an occasional glimmer of fertility [as compounds], the chemical equivalent of a blade of grass [in a desert]. So, gone … is the justification for “inert.” [Group 0 elements] are now known collectively as the noble gases, a name intended to imply a kind of chemical aloofness rather than a rigorous chastity.

This characteristic of modern experiments–that they consist principally of measurements,–is so prominent, that the opinion seems to have got abroad, that in a few years all the great physical constants will have been approximately estimated, and that the only occupation which will then be left to men of science will be to carry these measurements to another place of decimals … But we have no right to think thus of the unsearchable riches of creation, or of the untried fertility of those fresh minds into which these riches will continue to be poured.

To discover a Conception of the mind which will justly represent a train of observed facts is, in some measure, a process of conjecture, ... and the business of conjecture is commonly conducted by calling up before our minds several suppositions, selecting that one which most agrees with what we know of the observed facts. Hence he who has to discover the laws of nature may have to invent many suppositions before he hits upon the right one; and among the endowments which lead to his success, we must reckon that fertility of invention which ministers to him such imaginary schemes, till at last he finds the one which conforms to the true order of nature.

To fall back, to live on oneself, to withdraw is sterility. Communication with the exterior means fertility.

We have before us the restoration of that ancient land whose name was a synonym for abundance, prosperity, and grandeur for many generations. Records as old as those of Egypt and as well attested tell of fertile lands and teeming populations, mighty kings and warriors, sages and wise men, over periods of thousands of years. ... A land such as this is worth resuscitating. Once we have apprehended the true cause of its present desolate and abandoned condition, we are on our way to restoring it to its ancient fertility. A land which so readily responded to ancient science, and gave a return which sufficed for the maintenance of a Persian Court in all its splendor, will surely respond to the efforts of modern science and return manifold the money and talent spent on its regeneration.