Moira roperly signifies "a share," and as a personification " the deity who assigns to every man his fate or his share," or the Fates. Homer usually speaks of only one Moira, and only once mentions the Moirai in the plural. (Il. xxiv. 29.) In his poems Moira is fate personified, which, at the birth of man, spins out the thread of his future life (Il. xxiv. 209), follows his steps, and directs the consequences of his actions according to the counsel of the gods. (11. v. 613, xx. 5.) Homer thus, when he personifies Fate, conceives her as spinning, an act by which also the power of other gods over the life of man is expressed. (Il. xxiv. 525, Od. i. 17,iii. 208, iv. 208.) But the personification of his Moira is not complete, for he mentions no particular appearance of the goddess, no attributes, and no parentage; and his Moira is therefore quite synonymous with Aisa. (II. xx. 127, xxiv. 209.) If in Od. vii. 197, the Kataklôthes are the Moirae, and not the Eileithyiae, as some suppose, Aisa and Moira would indeed be two distinct beings, but still beings performing entirely the same functions.
The Homeric Moira is not, as some have thought, an inflexible fate, to which the gods themselves must bow; but, on the contrary, Zeus, as the father of gods and men, weighs out their fate to them (Il. viii. 69, xxii. 209; comp. xix. 108); and if he chooses, he has the power of saving even those who are already on the point of being seized by their fate (II. xvi. 434, 441, 443); nay, as Fate does not abruptly interfere in human affairs, but avails herself of intermediate causes, and determines the lot of mortals not absolutely, but only conditionally, even man himself, in his freedom, is allowed to exercise a certain influence upon her. (Od. i. 34, Il. ix. 411, xvi. 685.) As man's fate terminates at his death, the goddess of fate at the close of life becomes the goddess of death, moira thanatoio (Od. xxiv. 29, ii. 100, iii. 238), and is mentioned along with death itself, and with Apollo, the bringer of death. (Il. iii. 101, v. 83, xvi. 434, 853, xx. 477, xxi. 101, xxiv. 132.)
Hesiod (Theog. 217, &c., 904; comp. Apollod. i 3. § 1) has the personification of the Moirae complete; for he calls them, together with the Keres, daughters of Night; and distinguishes three, viz. Clotho, or the spinning fate; Lachesis, or the one who assigns to man his fate; and Atropos, or the fate that cannot be avoided. According to this genealogy, the Moirae must be considered as in a state of dependence upon their father, and as agreeing with his counsels. Hence he is called Moiragetês, i. e. the guide or leader of the Moirae (Paus. v. 15. § 4), and hence also they were represented along with their father in temples and works of art, as at Megara (Paus. i. 40. § 3), in the temple of Despoena in Arcadia (viii. 37. § 1), and at Delphi (x. 24. § 4; comp. viii. 42. § 2). They are further described as engraving on indestructible tables the decrees of their father Zeus. (Claudian, xv. 202; comp. Ov. Met. xv. 808, &c.) Later writers differ in their genealogy of the Moirae from that of Hesiod; thus they are called children of Erebus and Night (Cic. De Aat. Deor. iii. 17), of Cronos and Night (Tzetz. ad Lyc. 406), of Ge and Oceanus (Athenag. 15; Lycoph. 144), or lastly of Ananke or Necessity. (Plat. De Re Publ. p. 617, d.)
It cannot be surprising to find that the character and nature of the Moirae were conceived differently at different times and by different authors. Sometimes they appear as divinities of fate in the strict sense of the term, and sometimes only as allegorical divinities of the duration of human life. In the former character they are independent, at the helm of necessity, direct fate, and watch that the fate assigned to every being by eternal laws may take its course without obstruction (Aeschyl. Prom. 511, 515); and Zeus, as well as the other gods and men, must submit to them. (Herod. i. 91; Lactant. Institute. i. 11, 13; Stob. Eclog. i. pp. 152, 170.) They assign to the Erinnyes, who inflict the punishment for evil deeds, their proper functions; and with them they direct fate according to the laws of necessity, whence they are sometimes called the sisters of the Erinnyes. (Aeschyl. Eum. 335, 962, Prom. 516, 696, 895; Tzetz. ad Lyc. 406.) Later poets also conceive the Moirae in the same character. (Virg. Aen. v. 798, xii. 147; Tibull. i. 8. 2; Ov. Trist. v. 3. 17, Met. xv. 781; Horat. Carm. Saec. 25, &c.) These grave and mighty goddesses were represented by the earliest artists with staffs or sceptres, the symbol of dominion; and Plato (De Re Pub. p. 617) even mentions their crowns. (Mus. Pio-Clem. tom. vi. tab. B.)
The Moirae, as the divinities of the duration of human life, which is determined by the two points of birth and of death, are conceived either as goddesses of birth or as goddesses of death, and hence their number was two, as at Delphi. (Paus. x. 24. § 4; Plut. de Tranq. An. 15, de Ei ap. Delph. 2.) From this circumstance we may perhaps infer that originally the Greeks conceived of only one Moira, and that subsequently a consideration of her nature and attributes led to the belief in two, and ultimately in three Moirae; though a distribution of the functions among the three was not strictly observed, for in Ovid, for example (ad Liv. 239), and Tibullus (i. 8. 1.), all three are described as spinning, although this should be the function of Clotho alone, who is, in fact, often mentioned alone as the representative of all. (Pind. 01. i. 40; Ov. ad Liv. 164, Fast. vi. 757, Ex Pont. iv. 15. 36.) As goddesses of birth, who spill the thread of beginning life, and even prophesy the fate of the newly born, they are mentioned along with Eileithyia, who is called their companion and paredros. (Paus. viii. 21. § 2; Plat. Sympos. p. 206, d.; Pind. Ol. vi. 70, Nem. vii. 1; Anton. Lib. 29; comp. Eurip. Iphig. Taur. 207.) In a similar capacity they are also joined with Prometheus, the former, or creator of the human race in general. (Hygin. Poet. Astr. ii. 15.) The symbol with which they, or rather Clotho alone, are represented to indicate this function, is a spindle, and the idea implied in it was carried out so far, that sometimes we read of their breaking or cutting off the thread when life is to end. (Ov. Am. ii. 6. 46; Plat. de Re Publ. p. 616.) Being goddesses of fate, they must necessarily know the future, which at times they reveal, and thus become prophetic divinities. (Ov. Met. viii. 454, Trist. v. 3. 25; Tibull. i. 8. 1, iv. 5. 3; Catull. 64. 307.) As goddesses of death, they appear together with the Keres (Hes. Scut. Herc. 258) and the infernal Erinnyes, with whom they are even confounded, and in the neighbourhood of Sicyon the annual sacrifices offered to them were the same as those offered to the Erinnyes. (Paus. ii. 11. § 4; comp. Schol. ad Aesch. Agam. 70; Aelian, H. A. x. 33; Serv. ad Aen. i. 86.) It belongs to the same character that, along with the Charites, they lead Persephone out of the lower world into the regions of light, and are mentioned along with Pluto and Charon. (Orph. Hymn. 428; Ov. Fast. vi. 157; comp. Aristoph. Ran. 453.) The various epithets which poets apply to the Moirae generally refer to the severity, inflexibility, and sternness of fate.
They had sanctuaries in many parts of Greece, such as Corinth (Paus. ii. 4. § 7), Sparta (iii. 11. § 8), Olympia (v. 15. § 4), Thebes (ix. 2.5. § 4), and elsewhere. The poets sometimes describe them as aged and hideous women, and even as lame, to indicate the slow march of fate (Catull. 64, 306; Ov. Met. xv. 781; Tzetz. ad Lyc. 584) ; but in works of art they are represented as grave maidens, with different attributes, viz., Clotho with a spindle or a roll (the book of fate); Lachesis pointing with a staff to the horoscope on the globe ; and Atropos with a pair of scales, or a sun-dial, or a cutting instrument. It is worthy of remark that the Muse Urania was sometimes represented with the same attributes as Lachesis, and that Aphrodite Urania at Athens, according to an inscription on a Hermes-pillar, was called the oldest of the Moirae. (Paus. i. 19. § 2.)