Aristotle

by Various Works [lit]

  change,' holds in their case also.

  That many dreams have no fulfilment is not strange, for it is so too

  with many bodily toms and weather-signs, e.g. those of train or

  wind. For if another movement occurs more influential than that from

  which, while [the event to which it pointed was] still future, the

  given token was derived, the event [to which such token pointed]

  does not take place. So, of the things which ought to be

  accomplished by human agency, many, though well-planned are by the

  operation of other principles more powerful [than man's agency]

  brought to nought. For, speaking generally, that which was about to

  happen is not in every case what now is happening, nor is that which

  shall hereafter he identical with that which is now going to be.

  Still, however, we must hold that the beginnings from which, as we

  said, no consummation follows, are real beginnings, and these

  constitute natural tokens of certain events, even though the events do

  not come to pass.

  As for [prophetic] dreams which involve not such beginnings [sc.

  of future events] as we have here described, but such as are

  extravagant in times, or places, or magnitudes; or those involving

  beginnings which are not extravagant in any of these respects, while

  yet the persons who see the dream hold not in their own hands the

  beginnings [of the event to which it points]: unless the foresight

  which such dreams give is the result of pure coincidence, the

  following would be a better explanation of it than that proposed by

  Democritus, who alleges 'images' and 'emanations' as its cause. As,

  when something has caused motion in water or air, this [the portion of

  water or air], and, though the cause has ceased to operate, such

  motion propagates itself to a certain point, though there the prime

  movement is not present; just so it may well be that a movement and

  a consequent sense-perception should reach sleeping souls from the

  objects from which Democritus represents 'images' and 'emanations'

  coming; that such movements, in whatever way they arrive, should be

  more perceptible at night [than by day], because when proceeding

  thus in the daytime they are more liable to dissolution (since at

  night the air is less disturbed, there being then less wind); and that

  they shall be perceived within the body owing to sleep, since

  persons are more sensitive even to slight sensory movements when

  asleep than when awake. It is these movements then that cause

  'presentations', as a result of which sleepers foresee the future even

  relatively to such events as those referred to above. These

  considerations also explain why this experience befalls commonplace

  persons and not the most intelligent. For it would have regularly

  occurred both in the daytime and to the wise had it been God who

  sent it; but, as we have explained the matter, it is quite natural

  that commonplace persons should be those who have foresight [in

  dreams]. For the mind of such persons is not given to thinking, but,

  as it were, derelict, or totally vacant, and, when once set moving, is

  borne passively on in the direction taken by that which moves it. With

  regard to the fact that some persons who are liable to derangement

  have this foresight, its explanation is that their normal mental

  movements do not impede [the alien movements], but are beaten off by

  the latter. Therefore it is that they have an especially keen

  perception of the alien movements.

  That certain persons in particular should have vivid dreams, e.g.

  that familiar friends should thus have foresight in a special degree

  respecting one another, is due to the fact that such friends are

  most solicitous on one another's behalf. For as acquaintances in

  particular recognize and perceive one another a long way off, so

  also they do as regards the sensory movements respecting one

  another; for sensory movements which refer to persons familiarly known

  are themselves more familiar. Atrabilious persons, owing to their

  impetuosity, are, when they, as it were, shoot from a distance, expert

  at hitting; while, owing to their mutability, the series of

  movements deploys quickly before their minds. For even as the insane

  recite, or con over in thought, the poems of Philaegides, e.g. the

  Aphrodite, whose parts succeed in order of similitude, just so do they

  [the 'atrabilious'] go on and on stringing sensory movements together.

  Moreover, owing to their aforesaid impetuosity, one movement within

  them is not liable to be knocked out of its course by some other

  movement.

  The most skilful interpreter of dreams is he who has the faculty

  of observing resemblances. Any one may interpret dreams which are

  vivid and plain. But, speaking of 'resemblances', I mean that dream

  presentations are analogous to the forms reflected in water, as indeed

  we have already stated. In the latter case, if the motion in the water

  be great, the reflexion has no resemblance to its original, nor do the

  forms resemble the real objects. Skilful, indeed, would he be in

  interpreting such reflexions who could rapidly discern, and at a

  glance comprehend, the scattered and distorted fragments of such

  forms, so as to perceive that one of them represents a man, or a

  horse, Or anything whatever. Accordingly, in the other case also, in a

  similar way, some such thing as this [blurred image] is all that a

  dream amounts to; for the internal movement effaces the clearness of

  the dream.

  The questions, therefore, which we proposed as to the nature of

  sleep and the dream, and the cause to which each of them is due, and

  also as to divination as a result of dreams, in every form of it, have

  now been discussed.

  -THE END-

  .

  350 BC

  ON THE GENERATION OF ANIMALS

  by Aristotle

  translated by Arthur Platt

  Book I

  1

  WE have now discussed the other parts of animals, both generally and

  with reference to the peculiarities of each kind, explaining how

  each part exists on account of such a cause, and I mean by this the

  final cause.

  There are four causes underlying everything: first, the final cause,

  that for the sake of which a thing exists; secondly, the formal cause,

  the definition of its essence (and these two we may regard pretty

  much as one and the same); thirdly, the material; and fourthly, the

  moving principle or efficient cause.

  We have then already discussed the other three causes, for the

  definition and the final cause are the same, and the material of

  animals is their parts of the whole animal the non-homogeneous

  parts, of these again the homogeneous, and of these last the so-called

  elements of all matter. It remains to speak of those parts which

  contribute to the generation of animals and of which nothing

  definite has yet been said, and to explain what is the moving or

  efficient cause. To inquire into this last and to inquire into the

  generation of each animal is in a way the same thing; and,

  therefore, my
plan has united them together, arranging the

  discussion of these parts last, and the beginning of the question of

  generation next to them.

  Now some animals come into being from the union of male and

  female, i.e. all those kinds of animal which possess the two sexes.

  This is not the case with all of them; though in the sanguinea with

  few exceptions the creature, when its growth is complete, is either

  male or female, and though some bloodless animals have sexes so that

  they generate offspring of the same kind, yet other bloodless

  animals generate indeed, but not offspring of the same kind; such

  are all that come into being not from a union of the sexes, but from

  decaying earth and excrements. To speak generally, if we take all

  animals which change their locality, some by swimming, others by

  flying, others by walking, we find in these the two sexes, not only in

  the sanguinea but also in some of the bloodless animals; and this

  applies in the case of the latter sometimes to the whole class, as the

  cephalopoda and crustacea, but in the class of insects only to the

  majority. Of these, all which are produced by union of animals of

  the same kind generate also after their kind, but all which are not

  produced by animals, but from decaying matter, generate indeed, but

  produce another kind, and the offspring is neither male nor female;

  such are some of the insects. This is what might have been expected,

  for if those animals which are not produced by parents had

  themselves united and produced others, then their offspring must

  have been either like or unlike to themselves. If like, then their

  parents ought to have come into being in the same way; this is only

  a reasonable postulate to make, for it is plainly the case with

  other animals. If unlike, and yet able to copulate, then there would

  have come into being again from them another kind of creature and

  again another from these, and this would have gone on to infinity. But

  Nature flies from the infinite, for the infinite is unending or

  imperfect, and Nature ever seeks an end.

  But all those creatures which do not move, as the testacea and

  animals that live by clinging to something else, inasmuch as their

  nature resembles that of plants, have no sex any more than plants

  have, but as applied to them the word is only used in virtue of a

  similarity and analogy. For there is a slight distinction of this

  sort, since even in plants we find in the same kind some trees which

  bear fruit and others which, while bearing none themselves, yet

  contribute to the ripening of the fruits of those which do, as in

  the case of the fig-tree and caprifig.

  The same holds good also in plants, some coming into being from seed

  and others, as it were, by the spontaneous action of Nature, arising

  either from decomposition of the earth or of some parts in other

  plants, for some are not formed by themselves separately but are

  produced upon other trees, as the mistletoe. Plants, however, must

  be investigated separately.

  2

  Of the generation of animals we must speak as various questions

  arise in order in the case of each, and we must connect our account

  with what has been said. For, as we said above, the male and female

  principles may be put down first and foremost as origins of

  generation, the former as containing the efficient cause of

  generation, the latter the material of it. The most conclusive proof

  of this is drawn from considering how and whence comes the semen;

  for there is no doubt that it is out of this that those creatures

  are formed which are produced in the ordinary course of Nature; but we

  must observe carefully the way in which this semen actually comes into

  being from the male and female. For it is just because the semen is

  secreted from the two sexes, the secretion taking place in them and

  from them, that they are first principles of generation. For by a male

  animal we mean that which generates in another, and by a female that

  which generates in itself; wherefore men apply these terms to the

  macrocosm also, naming Earth mother as being female, but addressing

  Heaven and the Sun and other like entities as fathers, as causing

  generation.

  Male and female differ in their essence by each having a separate

  ability or faculty, and anatomically by certain parts; essentially the

  male is that which is able to generate in another, as said above;

  the female is that which is able to generate in itself and out of

  which comes into being the offspring previously existing in the

  parent. And since they are differentiated by an ability or faculty and

  by their function, and since instruments or organs are needed for

  all functioning, and since the bodily parts are the instruments or

  organs to serve the faculties, it follows that certain parts must

  exist for union of parents and production of offspring. And these must

  differ from each other, so that consequently the male will differ from

  the female. (For even though we speak of the animal as a whole as

  male or female, yet really it is not male or female in virtue of the

  whole of itself, but only in virtue of a certain faculty and a certain

  part- just as with the part used for sight or locomotion- which part

  is also plain to sense-perception.)

  Now as a matter of fact such parts are in the female the so-called

  uterus, in the male the testes and the penis, in all the sanguinea;

  for some of them have testes and others the corresponding passages.

  There are corresponding differences of male and female in all the

  bloodless animals also which have this division into opposite sexes.

  But if in the sanguinea it is the parts concerned in copulation that

  differ primarily in their forms, we must observe that a small change

  in a first principle is often attended by changes in other things

  depending on it. This is plain in the case of castrated animals,

  for, though only the generative part is disabled, yet pretty well

  the whole form of the animal changes in consequence so much that it

  seems to be female or not far short of it, and thus it is clear than

  an animal is not male or female in virtue of an isolated part or an

  isolated faculty. Clearly, then, the distinction of sex is a first

  principle; at any rate, when that which distinguishes male and

  female suffers change, many other changes accompany it, as would be

  the case if a first principle is changed.

  3

  The sanguinea are not all alike as regards testes and uterus. Taking

  the former first, we find that some of them have not testes at all, as

  the classes of fish and of serpents, but only two spermatic ducts.

  Others have testes indeed, but internally by the loin in the region of

  the kidneys, and from each of these a duct, as in the case of those

  animals which have no testes at all, these ducts unite also as with

  those animals; this applies (among animals breathing air and having a

  lung) to all birds and oviparous quadrupeds. For all these have their

  testes internal near the loin, and two ducts from these in the same

 
way as serpents; I mean the lizards and tortoises and all the scaly

  reptiles. But all the vivipara have their testes in front; some of

  them inside at the end of the abdomen, as the dolphin, not with

  ducts but with a penis projecting externally from them; others

  outside, either pendent as in man or towards the fundament as in

  swine. They have been discriminated more accurately in the Enquiries

  about Animals.

  The uterus is always double, just as the testes are always two in

  the male. It is situated either near the pudendum (as in women, and

  all those animals which bring forth alive not only externally but also

  internally, and all fish that lay eggs externally) or up towards

  the hypozoma (as in all birds and in viviparous fishes). The

  uterus is also double in the crustacea and the cephalopoda, for the

  membranes which include their so-called eggs are of the nature of a

  uterus. It is particularly hard to distinguish in the case of the

  poulps, so that it seems to be single, but the reason of this is

  that the bulk of the body is everywhere similar.

  It is double also in the larger insects; in the smaller the question

  is uncertain owing to the small size of the body.

  Such is the description of the aforesaid parts of animals.

  4

  With regard to the difference of the spermatic organs in males, if

  we are to investigate the causes of their existence, we must first

  grasp the final cause of the testes. Now if Nature makes everything

  either because it is necessary or because it is better so, this part

  also must be for one of these two reasons. But that it is not

  necessary for generation is plain; else had it been possessed by all

  creatures that generate, but as it is neither serpents have testes nor

  have fish; for they have been seen uniting and with their ducts full

  of milt. It remains then that it must be because it is somehow

  better so. Now it is true that the business of most animals is, you

  may say, nothing else than to produce young, as the business of a