“It would be quite false to say that competition is the only relation that obtains between species. Mutual dependence is in general quite as important. Each kind exists within an ecosystem, and needs the others to keep the system going. Thus, grazing animals on the African plains co-exist because each specializes in eating some particular kind of plant, and needs the others to keep the whole pasture at a balanced level. They depend, too, on each other's specialized capacities to give warning of danger. … each also depends for survival on innumerable others, such as the insects which pollinate the plants, the fauna of their intestines and of course their predators. It is unthinkable that any species should be an island.”

Source: 1890s, The Principles of Psychology (1890), Ch. 8

Source: Cosmos

Source: Competing on the Edge, 1998, p. 60

Source: General System Theory (1968), 2. The Meaning of General Systems Theory, p. 32

Source: SCUM MANIFESTO (1967), p. 7 (hyphens (not en- or em-dashes) so in original; "others" so in original, probably intended as "other's"; line break across "inter-"/"acting"; "noone" so in original, probably intended as "no one").

Source: Last and First Men (1930), Chapter III: America and China; Section 2, “The Conflict” (p. 50)

The Second Sex (1949)
Context: It is nonsense to assert that revelry, vice, ecstasy, passion, would become impossible if man and woman were equal in concrete matters; the contradictions that put the flesh in opposition to the spirit, the instant to time, the swoon of immanence to the challenge of transcendence, the absolute of pleasure to the nothingness of forgetting, will never be resolved; in sexuality will always be materialised the tension, the anguish, the joy, the frustration, and the triumph of existence. To emancipate woman is to refuse to confine her to the relations she bears to man, not to deny them to her; let her have her independent existence and she will continue none the less to exist for him also: mutually recognising each other as subject, each will yet remain for the other an other. The reciprocity of their relations will not do away with the miracles — desire, possession, love, dream, adventure — worked by the division of human beings into two separate categories; and the words that move us — giving, conquering, uniting — will not lose their meaning. On the contrary, when we abolish the slavery of half of humanity, together with the whole system of hypocrisy that it implies, then the 'division' of humanity will reveal its genuine significance and the human couple will find its true form.

1940s, Science and Religion (1941)
Context: Even though the realms of religion and science in themselves are clearly marked off from each other, nevertheless there exist between the two strong reciprocal relationships and dependencies. Though religion may be that which determines the goal, it has, nevertheless, learned from science, in the broadest sense, what means will contribute to the attainment of the goals it has set up. But science can only be created by those who are thoroughly imbued with the aspiration toward truth and understanding. This source of feeling, however, springs from the sphere of religion. To this there also belongs the faith in the possibility that the regulations valid for the world of existence are rational, that is, comprehensible to reason. I cannot conceive of a genuine scientist without that profound faith. The situation may be expressed by an image: science without religion is lame, religion without science is blind.
Though I have asserted above that in truth a legitimate conflict between religion and science cannot exist, I must nevertheless qualify this assertion once again on an essential point, with reference to the actual content of historical religions. This qualification has to do with the concept of God. During the youthful period of mankind's spiritual evolution human fantasy created gods in man's own image, who, by the operations of their will were supposed to determine, or at any rate to influence, the phenomenal world. Man sought to alter the disposition of these gods in his own favor by means of magic and prayer. The idea of God in the religions taught at present is a sublimation of that old concept of the gods. Its anthropomorphic character is shown, for instance, by the fact that men appeal to the Divine Being in prayers and plead for the fulfillment of their wishes.

Source: Reason: The Only Oracle Of Man (1784), Ch. III Section IV - Of Physical Evils
Context: Physical evils are in nature inseparable from animal life, they commenced existence with it, and are its concomitants through life; so that the same nature which gives being to the one, gives birth to the other also; the one is not before or after the other, but they are coexistent together, and contemporaries; and as they began existence in a necessary dependance on each other, so they terminate together in death and dissolution. This is the original order to which animal nature is subjected, as applied to every species of it. The beasts of the field, the fowls of the air, the fishes of the sea, with reptiles, and all manner of beings, which are possessed with animal life; nor is pain, sickness, or mortality any part of God's Punishment for sin. On the other hand sensual happiness is no part of the reward of virtue: to reward moral actions with a glass of wine or a shoulder of mutton, would be as inadequate, as to measure a triangle with sound, for virtue and vice pertain to the mind, and their merits or demerits have their just effects on the conscience, as has been before evinced: but animal gratifications are common to the human race indiscriminately, and also, to the beasts of the field: and physical evils as promiscuously and universally extend to the whole, so "That there is no knowing good or evil by all that is before us, for all is vanity." It was not among the number of possibles, that animal life should be exempted from mortality: omnipotence itself could not have made it capable of externalization and indissolubility; for the self same nature which constitutes animal life, subjects it to decay and dissolution; so that the one cannot be without the other, any more than there could be a compact number of mountains without valleys, or that I could exist and not exist at the same time, or that God should effect any other contradiction in nature...