1. We will first suppose the case of an interior growth occurring, the nature of which cannot be determined. It may be only a tumor, yet it may be the growth of a living fœtus. If no immediate crisis is feared, you will wait, of course, for further developments. If it proves to be a child, you will attempt no operation till it becomes viable at least. But suppose that fatal consequences are apprehended before the presence of a human being can be ascertained by the beating of the heart; suppose that delay would endanger the mother's life; and yet if you undertake to cut out the tumor, you may find it to contain fœtal life. In such urgent danger, can you lawfully perform the operation? Let us apply our principles. You mean to operate on a tumor affecting one of the mother's organs. The consequences this may have for the child are not directly willed, but permitted. The four conditions mentioned before are hereby verified, under which the evil result, the death of the possible fœtus, may be lawfully permitted; namely: (_a_) You do not wish its death; (_b_) What you intend directly, the operation on the mother's organism, is good in itself; (_c_) The good effect intended, her safety, to which she has an undoubted right, overbalances the evil effect, the possible death of the child, whose right to life is doubtful, since its very existence is doubtful; now, a certain right must take precedence of a doubtful right of the same species; (_d_) The evil is not made the means to obtain the good effect (see "Am. Eccl. Rev.," Nov., 1893, p. 353). This last condition would not be verified if it were proposed, not to cut out the cyst, but to destroy its contents by an electric current. Then, it would seem, the fœtus itself, if there be one, would be directly attacked.