Life and Habit

by Samuel Butler

A medusa begets a ciliated larva, the larva begets a polyp, the polyp begets a strobila, and the strobila begets a medusa again; the cycle of reproduction being completed in the fourth generation.

A frog lays an egg, which egg becomes a tadpole; the tadpole, after more or fewer intermediate stages, becomes a frog.

The mammals lay eggs, which they hatch inside their own bodies, instead of outside them; but the difference is one of degree and not of kind. In all these cases how difficult is it to say where identity begins or ends, or again where death begins or ends, or where reproduction begins or ends.

How small and unimportant is the difference between the changes which a caterpillar undergoes before becoming a moth, and those of a strobila before becoming a medusa. Yet in the one case we say the caterpillar does not die, but is changed (though, if the various changes in its existence be produced metagenetically, as is the case with many insects, it would appear to make a clean sweep of every organ of its existence, and start de novo, growing a head where its feet were, and so on—at least twice between its lives as caterpillar and butterfly); in this case, however, we say the caterpillar does not die, but is changed; being, nevertheless, one personality with the moth, into which it is developed. But in the case of the strobila we say that it is not changed, but dies, and is no part of the personality of the medusa.

We say the egg becomes the caterpillar, not by the death of the egg and birth of the caterpillar, but by the ordinary process of nutrition and waste—waste and repair—waste and repair continually. In like manner we say the caterpillar becomes the chrysalis, and the chrysalis the moth, not through the death of either one or the other, but by the development of the same creature, and the ordinary processes of waste and repair. But the medusa after three or four cycles becomes the medusa again, not, we say, by these same processes of nutrition and waste, but by a series of generations, each one involving an actual birth and an actual death. Why this difference? Surely only because the changes in the offspring of the medusa are marked by the leaving a little more husk behind them, and that husk less shrivelled, than is left on the occasion of each change between the caterpillar and the butterfly. A little more residuum, which residuum, it may be, can move about; and though shrivelling from hour to hour, may yet leave a little more offspring before it is reduced to powder; or again, perhaps, because in the one case, though the actors are changed, they are changed behind the scenes, and come on in parts and dresses, more nearly resembling those of the original actors, than in the other.

When the caterpillar emerges from the egg, almost all that was inside the egg has become caterpillar; the shell is nearly empty, and cannot move; therefore we do not count it, and call the caterpillar a continuation of the egg’s existence, and personally identical with the egg. So with the chrysalis and the moth; but after the moth has laid her eggs she can still move her wings about, and she looks nearly as large as she did before she laid them; besides, she may yet lay a few more, therefore we do not consider the moth’s life as continued in the life of her eggs, but rather in their husk, which we still call the moth, and which we say dies in a day or two, and there is an end of it. Moreover, if we hold the moth’s life to be continued in that of her eggs, we shall be forced to admit her to be personally identical with each single egg, and, hence, each egg to be identical with every other egg, as far as the past, and community of memories, are concerned; and it is not easy at first to break the spell which words have cast around us, and to feel that one person may become many persons, and that many different persons may be practically one and the same person, as far as their past experience is concerned; and again, that two or more persons may unite and become one person, with the memories and experiences of both, though this has been actually the case with every one of us.

Our present way of looking at these matters is perfectly right and reasonable, so long as we bear in mind that it is a façon de parler, a sort of hieroglyphic which shall stand for the course of nature, but nothing more. Repair (as is now universally admitted by physiologists) is only a phase of reproduction, or rather reproduction and repair are only phases of the same power; and again, death and the ordinary daily waste of tissue, are phases of the same thing. As for identity it is determined in any true sense of the word, not by death alone, but by a combination of death and failure of issue, whether of mind or body.

To repeat. Wherever there is a separate centre of thought and action, we see that it is connected with its successive stages of being, by a series of infinitely small changes from moment to moment, with, perhaps, at times more startling and rapid changes, but, nevertheless, with no such sudden, complete, and unrepaired break up of the preceding condition, as we shall agree in calling death. The branching out from it at different times of new centres of thought and action, has commonly as little appreciable effect upon the parent-stock as the fall of an apple full of ripe seeds has upon an apple-tree; and though the life of the parent, from the date of the branching off of such personalities, is more truly continued in these than in the residuum of its own life, we should find ourselves involved in a good deal of trouble if we were commonly to take this view of the matter. The residuum has generally the upper hand. He has more money, and can eat up his new life more easily than his new life, him. A moral residuum will therefore prefer to see the remainder of his life in his own person, than in that of his descendants, and will act accordingly. Hence we, in common with most other living beings, ignore the offspring as forming part of the personality of the parent, except in so far as that we make the father liable for its support and for its extravagances (than which no greater proof need be wished that the law is at heart a philosopher, and perceives the completeness of the personal identity between father and son) for twenty-one years from birth. In other respects we are accustomed, probably rather from considerations of practical convenience than as the result of pure reason, to ignore the identity between parent and offspring as completely as we ignore personality before birth. With these exceptions, however, the common opinion concerning personal identity is reasonable enough, and is found to consist neither in consciousness of such identity, nor yet in the power of recollecting its various phases (for it is plain that identity survives the distinction or suspension of both these), but in the fact that the various stages appear to the majority of people to have been in some way or other linked together.

For a very little reflection will show that identity, as commonly predicated of living agents, does not consist in identity of matter, of which there is no same particle in the infant, we will say, and the octogenarian into whom he has developed. Nor, again, does it depend upon sameness of form or fashion; for personality is felt to survive frequent and radical modification of structure, as in the case of caterpillars and other insects. Mr. Darwin, quoting from Professor Owen, tells us (Plants and Animals under Domestication, vol. ii. p. 362, ed. 1875), that in the case of what is called metagenetic development, “the new parts are not moulded upon the inner surfaces of the old ones. The plastic force has changed its mode of operation. The outer case, and all that gave form and character to the precedent individual, perish, and are cast off; they are not changed into the corresponding parts of the same individual. These are due to a new and distinct developmental process.” Assuredly, there is more birth and death in the world than is dreamt of by the greater part of us; but it is so masked, and on the whole, so little to our purpose, that we fail to see it. Yet radical and sweeping as the changes of organism above described must be, we do not feel them to be more a bar to personal identity than the considerable changes which take place in the structure of our own bodies between youth and old age.

Perhaps the most striking illustration of this is to be found in the case of some Echinoderms, concerning which Mr. Darwin tells us, that “the animal in the second stage of development is formed almost like a bud within the animal of the first stage, the latter being then cast off like an old vestment, yet sometimes maintaining for a short period an independent vitality” (“Plants and Animals under Domestication,” vol. ii. p. 362, ed. 1875).