IMMERSION (Lat. immersio, dipping), the act of being plunged into a fluid, or being overwhelmed by anything; in astronomy, the disappearance of a heavenly body in the shadow of another, especially of a satellite in the shadow of its primary.
IMMIGRATION (from Lat. in, into, and migrare, to depart), the movement of population, other than that of casual visitors or travellers, into one country from another (see [Migration]).
IMMORTALITY (Lat. in-, not, mortalis, mortal, from mors, death), the condition or quality of being exempt from death or annihilation. This condition has been predicated of man, both body and soul, in many senses; and the term is used by analogy of those whose deeds or writings have made a lasting impression on the memory of man. The belief in human immortality in some form is almost universal; even in early animistic cults the germ of the idea is present, and in all the higher religions it is an important feature. This article is confined to summarizing the philosophical or scientific arguments for, and objections to, the doctrine of the persistence of the human soul after death. For the Christian doctrine, see [Eschatology]; and for other religions see the separate articles.
In the Orphic mysteries “the soul was regarded as a part of the divine, a particula aurae divinae, for which the body in its limited and perishable condition was no fit organ, but a grave or prison (τὸ σῶμα σῆμα). The existence of the soul in the body was its punishment for sins in a previous condition; and the doom of its sins in the body was its descent into other bodies, and the postponement of its deliverance” (Salmond’s Christian Doctrine of Immortality, p. 109). This deliverance was what the mysteries promised. A remarkable passage in Pindar (Thren. 2) is thus rendered by J. W. Donaldson (Pindar’s Epinician or Triumphal Odes, p. 372). “By a happy lot, all persons travel to an end free of toil. And the body, indeed, is subject to the powerful influence of death; but a shadow of vitality is still left alive, and this alone is of divine origin; while our limbs are in activity it sleeps; but, when we sleep, it discloses to the mind in many dreams the future judgment with regard to happiness and misery.”
The belief of Socrates is uncertain. In the Apology he is represented as sure that “no evil can happen to a good man, either in life or after death,” but as not knowing whether “death be a state of nothingness and utter unconsciousness, or a change or migration of the soul from this world to the next” (i. 40, 41). In the Phaedo a confident expectation is ascribed to him. He is not the body to be buried; he will not remain with his friends after he has drunk the poison, but he will go away to the happiness of the blessed. The silence of the Memorabilia of Xenophon must be admitted as an argument to the contrary; but the probability seems to be that Plato did not in the Phaedo altogether misrepresent the Master. In Plato’s thought the belief held a prominent position. “It is noteworthy,” says Professor D. G. Ritchie, “that, in the various dialogues in which Plato speaks of immortality, the arguments seem to be of different kinds, and most of them quite unconnected with one another.” In the Phaedrus (245 C) the argument is, that the soul is self-moving, and, therefore, immortal; and this argument is repeated in the Laws (x. 894, 895). It is an argument that Plato probably inherited from Alcmaeon, the physician of Croton (Arist. De An. i. 2, § 17 405 A 29), whose views were closely connected with those of the Pythagoreans. In the Phaedo the main argument up to which all the others lead is that the soul participates in the idea of life. Recollection (anamnesis) alone would prove pre-existence, but not existence after death. In the tenth book of the Republic we find the curious argument that the soul does not perish like the body, because its characteristic evil, sin or wickedness does not kill it as the diseases of the body wear out the bodily life. In the Timaeus (41 A) the immortality even of the gods is made dependent on the will of the Supreme Creator; souls are not in their own nature indestructible, but persist because of His goodness. In the Laws (xii. 959 A) the notion of a future life seems to be treated as a salutary doctrine which is to be believed because the legislator enacts it (Plato, p. 146). The estimate to be formed of this reasoning has been well stated by Dr A. M. Fairbairn, “Plato’s arguments for immortality, isolated, modernized, may be feeble, even valueless, but allowed to stand where and as he himself puts them, they have an altogether different worth. The ratiocinative parts of the Phaedo thrown into syllogisms may be easily demolished by a hostile logician; but in the dialogue as a whole there is a subtle spirit and cumulative force which logic can neither seize nor answer” (Studies in the Philosophy of Religion, p. 226, 1876).
Aristotle held that the νοῦς or active intelligence alone is immortal. The Stoics were not agreed upon the question. Cleanthes is said to have held that all survive to the great conflagration which closes the cycle, Chrysippus that only the wise will. Marcus Aurelius teaches that even if the spirit survive for a time it is at last “absorbed in the generative principle of the universe.” Epicureanism thought that “the wise man fears not death, before which most men tremble; for, if we are, it is not; if it is, we are not.” Death is extinction. Augustine adopts a Platonic thought when he teaches that the immortality of the soul follows from its participation in the eternal truths. The Apologists themselves welcomed, and commended to others, the Christian revelation as affording a certainty of immortality such as reason could not give. The Aristotelian school in Islam did not speak with one voice upon the question; Avicenna declared the soul immortal, but Averroes assumes only the eternity of the universal intellect. Albertus Magnus argued that the soul is immortal, as ex se ipsa causa, and as independent of the body; Pietro Pomponazzi maintained that the soul’s immortality could be neither proved nor disproved by any natural reasons. Spinoza, while consistently with his pantheism denying personal immortality, affirms that “the human mind cannot be absolutely destroyed with the body, but there remains of it something which is eternal” (Eth. v. prop, xxiii.). The reason he gives is that, as this something “appertains to the essence of the mind,” it is “conceived by a certain eternal necessity through the very essence of God.”
Leibnitz, in accord with the distinctive principle of his philosophy, affirmed the absolute independence of mind and body as distinct monads, the parallelism of their functions in life being due to the pre-established harmony. For the soul, by its nature as a single monad indestructible and, therefore, immortal, death meant only the loss of the monads constituting the body and its return to the pre-existent state. The argument of Ernst Platner (Philos. Aphor. i. 1174, 1178) is similar. “If the human soul is a force in the narrower sense, a substance, and not a combination of substances, then, as in the nature of things there is no transition from existence to non-existence, we cannot naturally conceive the end of its existence, any more than we can anticipate a gradual annihilation of its existence.” He adds a reason that recalls one of Plato’s, “As manifestly as the human soul is by means of the senses linked to the present life, so manifestly it attaches itself by reason, and the conceptions, conclusions, anticipations and efforts to which reason leads it, to God and eternity.”
Against the first kind of argument, as formulated by Moses Mendelssohn, Kant advances the objection that, although we may deny the soul extensive quantity, division into parts, yet we cannot refuse to it intensive quantity, degrees of reality; and consequently its existence may be terminated not by decomposition, but by gradual diminution of its powers (or to use the term he coined for the purpose, by elanguescence). This denial of any reasonable ground for belief in immortality in the Critique of Pure Reason (Transcendental Dialectic, bk. ii. ch. i.) is, however, not his last word on the subject. In the Critique of the Practical Reason (Dialectic, ch. i. sec. iv) the immortality of the soul is shown to be a postulate. Holiness, “the perfect accordance of the will with the moral law,” demands an endless progress; and “this endless progress is only possible on the supposition of an endless duration of the existence and personality of the same rational being (which is called the immortality of the soul).” Not demonstrable as a theoretical proposition, the immortality of the soul “is an inseparable result of an unconditional a priori practical law.” The moral interest, which is so decisive on this question in the case of Kant, dominates Bishop Butler also. A future life for him is important, because our happiness in it may depend on our present conduct; and therefore our action here should take into account the reward or punishment that it may bring on us hereafter. As he maintains that probability may and ought to be our guide in life, he is content with proving in the first chapter of the Analogy that “a future life is probable from similar changes (as death) already undergone in ourselves and in others, and from our present powers, which are likely to continue unless death destroy them.” While we may fear this, “there is no proof that it will, either from the nature of death,” of the effect of which on our powers we are altogether ignorant, “or from the analogy of nature, which shows only that the sensible proof of our powers (not the powers themselves) may be destroyed.” The imagination that death will destroy these powers is unfounded, because (1) “this supposes we are compounded, and so discerptible, but the contrary is probable” on metaphysical grounds (the indivisibility of the subject in which consciousness as indivisible inheres, and its distinction from the body) and also experimental (the persistence of the living being in spite of changes in the body or even losses of parts of the body); (2) this also assumes that “our present living powers of reflection” must be affected in the same way by death “as those of sensation,” but this is disproved by their relative independence even in this life; (3) “even the suspension of our present powers of reflection” is not involved in “the idea of death, which is simply dissolution of the body,” and which may even “be like birth, a continuation and perfecting of our powers.” “Even if suspension were involved, we cannot infer destruction from it” (analysis of chapter i. in Angus’s edition). He recognizes that “reason did, as it well might, conclude that it should finally, and upon the whole, be well with the righteous and ill with the wicked,” but only “revelation teaches us that the next state of things after the present is appointed for the execution of this justice” (ch. ii. note 10). He does not use this general anticipation of future judgment, as he might have done, as a positive argument for immortality.