Also 7 aiti-, 8 eti- [ad. L. ætiologia, a. Gr. αἰτιολογία giving a cause, f. αἰτία cause, reason + -λογία discourse: see -LOGY.]
1. The assignment of a cause, the rendering of a reason; also, the reason annexed, the wherefore of a command or utterance.
a. 1555. Bradford, Wks., 44. He addeth this ætiology or cause, saying, ‘For the kingdom of heaven is at hand.’
1615. Bp. Hall, Contempl., IV. xi. (1853), 279. And consider with me the topography, the aitiology, the chronography of this miracle.
1716. Halley, in Phil. Trans., XXIX. 406. The Etiology of a matter so uncommon, never before seen by my self.
1771. Woulfe, ibid., LXI. 115. Ætiology of the Operation.
Mod. Title of a lecture: ‘The ætiology of the drinking customs.’
2. The science or philosophy of causation; that part of philosophy that treats of the demonstration of causes; the part of any special science that speculates on the causes of its phenomena.
1660. T. Stanley, Hist. Philos. (1701), 486/2. Whereby he conceives all Dogmatick Etiology may be refelled, as defective.
1753. Chambers, Cycl. Supp., s.v., The sceptics were professed opponents of all ætiology, or argumentation from causes.
1877. Huxley, Anat. Inv. Anim., Introd. 35. Ætiology has for its object the ascertainment of the causes of these facts, and the explanation of biological phenomena, by showing that they constitute particular cases of general physical laws.
3. That branch of medical science that investigates the causes and origin of diseases; the scientific exposition of the origin of any disease.
1684. trans. Bonet’s Merc. Compit., XVI. 562. Nor will it be easie … to inquire the particular reasons of this Ail, nor to proceed in this Aitiology.
1737. R. Bracken, Farriery, I. vi. 36. The Aetiology or Doctrine teaching (or rather pretending to teach) us the Knowledge of the Causes of Distempers.
1881. Huxley, in Nature, No. 615. 346. The important part played by parasitic organisms in the ætiology of disease.
