The Works of William Harvey M.D. / Translated from the Latin with a life of the author

by William Harvey

But where this contagion lies hid in the female after intercourse, and how it is communicated and given to the egg, demands quite a special inquiry, and we shall have occasion to treat of the matter when we come to discuss the conception of females in general. It will suffice, meantime, if we say that the same law applies to the prime efficient—in which inheres the reason of the future offspring—as to the offspring; as this is of a mixed nature, the nature of its cause must also be mixed; and it must either proceed equally from both parents, or from something else which is employed by both concurrently as instruments, animated, co-operating, mixed, and in the sexual act coalescing unto one. And this is the third condition of the prime efficient, that it either imparts motion to all the intermediate instruments in succession, or uses them in some other way, but comes not itself into play. Whence the origin of the doubt that has arisen, whether, in the generation of the chick, the cock were the true prime efficient, or whether there were not another prior, superior to him? For, indeed, all things seem to derive their origin from a celestial influence, and to follow the movements of the sun and moon. But we shall be able to speak more positively of this matter after we have shown what we understand by the “instrument,” or “instrumental efficient cause,” and how it is subdivided.

Instrumental efficients, then, are of different kinds: some, according to Aristotle, are factive, others active; some have no capacity any way unless conjoined with another prior efficient, as the hand, foot, genital organs, &c. with the rest of the body; others have an influence even when separate and distinct, as the seminal fluid and the ovum. Some instruments, again, have neither motion nor action beyond those that are imparted to them by the prime efficient; and others have peculiar inherent principles of action, to which nature indeed allows no motion in the business of generation, though she still uses their faculties, and prescribes them laws or limits in their operations, not otherwise than the cook makes use of fire in cooking, and the physician of herbs and drugs in curing diseases.

Sennert, that he may uphold the opinion he had espoused of the vital principle (anima) being present in the semen, and the formative faculty of the chick being extant in the egg, asserts that not only is the egg, but the semen of the cock, endowed with the living principle of the future chick. Moreover, he distinctly denies that there is any separate instrumental efficient; and says, that that only ought to be entitled “instrument” which is conjoined with the prime efficient; and that only “instrumental efficient,” which has no motion or action save that which is imparted to it by the prime efficient, or which is continuously and successively received, and in virtue of which it acts. And on this ground he rejects the example of projectiles, which have received force from the projecting agent, and, separated from it, act nevertheless; as if swords and spears were properly to be called warlike weapons, but arrows and bullets to be refused this title. He also rejects the argument derived from the republic, denying thereby that magistrates, counsellors, or ministers, are instruments of government; although Aristotle regards a counsel as an efficient, and in express terms calls a minister an instrument.[269] Sennert likewise denies the example of automata; and says and gainsays much besides, with a view to confirming himself in his position, that the semen and the egg are possessed of a living principle (anima), and are not mediate or instrumental, but principal agents. Sennert, nevertheless, as it were compelled by the force of truth, lays down such conditions for a principal agent, as fully and effectually contradict all that he had said before. He tells us, for instance, that “whatever produces a work or an effect more noble than itself, or an effect unlike itself, is not a principal efficient, but an instrumental cause;” granting which, who would not infer that the semen and the egg were instruments? seeing that the pullet is an effect more noble than the egg, and every way unlike either this or the spermatic fluid. Wherefore, when the learned Sennert denies the semen and the egg to be instruments or organs, because they are distinct from the prime agents, he takes his position upon a false basis; because, as the prime generator procreates offspring by various means or media, the medium being here conjunct, as the hand of the workman is with his body, there separate and distinct, as is the arrow let loose from the bow, it is still to be regarded as an instrument.

From the conditions now enumerated of an instrumental cause, it seems to follow that the prime efficient in the generation of the chick is the cock, or, at all events, the cock and hen, because the resulting pullet resembles these; nor can it be held more noble than they, which are its prime efficients or parents. I shall, therefore, add another condition of the prime efficient, whence it may, perhaps, appear that the male is not the prime, but only the instrumental, cause of the chick; viz., that the prime efficient in the formation of the chick makes use of artifice, and foresight, and wisdom, and goodness, and intelligence, which far surpass the powers of our rational soul to comprehend, inasmuch as all things are disposed and perfected in harmony with the purpose of the future work, and that there be action to a determinate end; so that every, even the smallest, part of the chick is fashioned for the sake of a special use and end, and with respect not merely to the rearing of the fabric, but also to its well-being, and elegance and preservation. But the male or his semen is not such either in the act of kind or after it, that art, intelligence, and foresight can be ascribed to him or it.

The proper inference from these premises appears to be that the male, as well as his seminal fluid, is the efficient instrument; and the female not less than the egg she lays the same. Wherefore, we have to seek refuge in a prior, superior, and more excellent cause, to which, with all propriety, are ascribed foresight, intelligence, goodness, and skill, and which is by so much more excellent than its effect or work, as the architect is more worthy than the pile he rears, as the king is more exalted than his minister, as the workman is better than his hands or tools.

The male and female, therefore, will come to be regarded as merely the efficient instruments, subservient in all respects to the Supreme Creator, or father of all things. In this sense, consequently, it is well said that the sun and moon engender man; because, with the advent and secession of the sun, come spring and autumn, seasons which mostly correspond with the generation and decay of animated beings. So that the great leader in philosophy says:[270] “The first motion [of the sphere?] is not the cause of generation and destruction; it is the motion of the ecliptic that is so, this being both continuous and having two movements; for, if future generation and corruption are to be eternal, it is necessary that something likewise move eternally, that interchanges do not fail, that of the two actions one only do not occur. The cause of the perpetuity [of animal species?] is, therefore, the law of the universe; and the obliquity [of the ecliptic?] is the cause of the approach and accession, [of the sun?] and of his being now nearer, now more remote: when he quits us, and removes to a distance, it is then that decay and corruption intervene; and, in like manner, when he approaches, it is then that he engenders; and if, as he frequently approaches, he engenders; so, because he frequently recedes, does he cause corruption; for the causes of contraries are contrary.”

All things, therefore, grow and flourish in spring, (on the approach of the sun, that is to say, he being the common parent and producer, or at all events the immediate and universal instrument of the Creator in the work of reproduction); and this is true not of plants only but of animals also; nor less of those that come spontaneously, than of those that are propagated by the consentient act of male and female. It is as if, with the advent of this glorious luminary, Venus the bountiful descended from heaven, waited on by Cupid and a cohort of graces, and prompted all living things by the bland incitement of love to secure the perpetuity of their kinds. Or (and it is thus that we have it in the mythology) it is as if the genital organs of Saturn, cast into the sea at this season, raised a foam, whence sprung Aphrodite. For, in the generation of animals, as the poet says, “superat tener omnibus humor,”—a gentle moisture all pervades,—and the genitals froth and are replete with semen.

The cock and the hen are especially fertile in the spring; as if the sun, or heaven, or nature, or the soul of the world, or the omnipotent God—for all these names signify the same thing—were a cause in generation superior and more divine than they; and thus it is that the sun and man, i.e. the sun through man as the instrument, engender man. In the same way the preserver of all things, and the male among birds, give birth to the egg, from whence the chick, the perfect bird, is made eternal in its kind by the approach and recession of the god of day, who, by the divine will and pleasure, or by fate, serves for the generation of all that lives.

Let us conclude, therefore, that the male, although a prior and more excellent efficient than the female, is still no more than an instrumental efficient, and that he, not less than the female, must refer his fecundity or faculty of engendering as received from the approaching sun; and, consequently, that the skill and foresight, which are apparent in his work, are not to be held as proceeding from him but from God; inasmuch as the male in the act of kind neither uses counsel nor understanding; neither does man engender the rational part of his soul, but only the vegetative faculty; which is not regarded as any principal or more divine faculty of the soul, but one only of a lower order.

Since, then, there is not less of skill and prescience manifested in the structure of the chick than in the creation of man and the universe at large, it is imperative even in the generation of man to admit an efficient cause, superior to, and more excellent than man himself: otherwise the vegetative faculty, or that part of the soul or living principle which fashions and preserves a man, would have to be accounted far more excellent and divine, and held to bear a closer resemblance to God than the rational portion of the soul, whose excellence, nevertheless, we extol over all the faculties of all animals, and esteem as that which has right and empire in them, and to which all created things are made subservient. Or we should else have to own that in the works of nature there was neither prudence, nor art, nor understanding; but that these appeared to us, who are wont to judge of the divine things of nature after our own poor arts and faculties, or to contrast them with examples due to ourselves; as if the active principles of nature produced their effects in the same way as we are used to produce our artificial works, by counsel, to wit, or discipline acquired through the mind or understanding.