text: Abortion? Even sheep, don't do that. [ Footnote 22 ] Early philosophers believed that the embryo or fetus did not become formed and begin to live until at least 40 days after conception for a male, and 80 to 90 days for a female. See, for example, Aristotle, Hist. Anim. 7.3.583b; Gen. Anim. 2.3.736, 2.5.741; Hippocrates, Lib. de Nat. Puer., No. 10. Aristotle's thinking derived from his three-stage theory of life: vegetable, animal, rational. The vegetable stage was reached at conception, the animal at "animation," and the rational soon after live birth. This theory, together with the 40/80 day view, came to be accepted by early Christian thinkers...MR. JUSTICE REHNQUIST, dissenThe Court's opinion brings to the decision of this troubling question both extensive historical fact and a wealth of legal scholarship...
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