Hints towards the formation of a more comprehensive theory of life/The Nature of Life/Part 2

Previously to the submitting my own ideas on the subject of life, and the powers into which it resolves itself, or rather in which it is manifested to us, I have hazarded this apparent digression from the anxiety to preclude certain suspicions, which the subject itself is so fitted to awaken, and while I anticipate the charges, to plead in answer to each a full and unequivocal—not guilty!

In the first place, therefore, I distinctly disclaim all intention of explaining life into an occult quality; and retort the charge on those who can satisfy themselves with defining it as the peculiar power by which death is resisted.

Secondly. Convinced—by revelation, by the consenting authority of all countries, and of all ages, by the imperative voice of my own conscience, and by that wide chasm between man and the noblest animals of the brute creation, which no perceivable or conceivable difference of organization is sufficient to overbridge—that I have a rational and responsible soul, I think far too reverentially of the same to degrade it into an hypothesis, and cannot be blind to the contradiction I must incur, if I assign that soul which I believe to constitute the peculiar nature of man as the cause of functions and properties, which man possesses in common with the oyster and the mushroom.[1]

Thirdly, while I disclaim the error of Stahl in deriving the phenomena of life from the unconscious actions of the rational soul, I repel with still greater earnestness the assertion and even the supposition that the functions are the offspring of the structure, and "Life[2] the result of organization," connected with it as effect with cause. Nay, the position seems to me little less strange, than as if a man should say, that building with all the included handicraft, of plastering, sawing, planing, &c. were the offspring of the house; and that the mason and carpenter were the result of a suite of chambers, with the passages and staircases that lead to them. To make a the offspring of b, when the very existence of b as b presupposes the existence of a, is preposterous in the literal sense of the word, and a consummate instance of the hysteron proteron in logic. But if I reject the organ as the cause of that, of which it is the organ, though I might admit it among the conditions of its actual functions; for the same reason, I must reject fluids and ethers of all kinds, magnetical, electrical, and universal, to whatever quintessential thinness they may be treble distilled, and (as it were) super-substantiated. With these, I abjure likewise all chemical agencies, compositions, and decompositions, were it only that as stimulants they suppose a stimulability sui generis, which is but another paraphrase for life. Or if they are themselves at once both the excitant and the excitability, I miss the connecting link between this imaginary ether and the visible body, which then becomes no otherwise distinguished from inanimate matter, than by its juxtaposition in mere space, with an heterogeneous inmate, the cycle of whose actions revolves within itself. Besides which I should think that I was confounding metaphors and realities most absurdly, if I imagined that I had a greater insight into the meaning and possibility of a living alcohol, than of a living quicksilver. In short, visible surface and power of any kind, much more the power of life, are ideas which the very forms of the human understanding make it impossible to identify. But whether the powers which manifest themselves to us under certain conditions in the forms of electricity, or chemical attraction, have any analogy to the power which manifests itself in growth and organization, is altogether a different question, and demands altogether a different chain of reasoning: if it be indeed a tree of knowledge, it will be known by its fruits, and these will depends not on the mere assertion, but on the inductions by which the position is supported, and by the additions which it makes to our insight into the nature of the facts it is meant to illustrate.

To account for Life is one thing; to explain Life another. In the first we are supposed to state something prior (if not in time, yet in the order of Nature) to the thing accounted for, as the ground or cause of that thing, or (which comprises the meaning and force of both words) as its sufficient cause, quæ et facit, et subest. And to this, in the question of Life, I know no possible answer, but God. To account for a thing is to see into the principle of its possibility, and from that principle to evolve its being. Thus the mathematician demonstrates the truths of geometry by constructing them. It is an admirable remark of Joh. Bapt. a Vico, in a Tract published at Naples, 1710,[3] "Geometrica ideò demonstramus, quia facimus; physica si demonstrare possimus, faceremus. Metaphysici veri claritas eadem ac lucis, quam non nisi per opaca cognoscimus; nam non lucem sed lucidas res videmus. Physica sunt opaca, nempe formata et finita, in quibus Metaphysici veri lumen videmus." The reasoner who assigns structure or organization as the antecedent of Life, who names the former a cause, and the latter its effect, he it is who pretends to account for life. Now Euclid would, with great right, demand of such a philosopher to make Life; in the same sense, I mean, in which Euclid makes an Icosaedron, or a figure of twenty sides, namely, in the understanding or by an intellectual construction. An argument which, of itself, is sufficient to prove the untenable nature of Materialism.

To explain a power, on the other hand, is (the power itself being assumed, though not comprehended, ut qui datur, non intelligitur) to unfold or spread it out: ex implicito planum facere. In the present instance, such an explanation would consist in the reduction of the idea of Life to its simplest and most comprehensive form or mode of action; that is, to some characteristic instinct or tendency, evident in all its manifestations, and involved in the idea itself. This assumed as existing in kind, it will be required to present an ascending series of corresponding phenomena as involved in, proceeding from, and so far therefore explained by, the supposition of its progressive intensity and of the gradual enlargement of its sphere, the necessity of which again must be contained in the idea of the tendency itself. In other words, the tendency having been given in kind, it is required to render the phenomena intelligible as its different degrees and modifications. Still more perfect will the explanation be, should the necessity of this progression and of these ascending gradations be contained in the assumed idea of life, as thus defined by the general form and common purport of all its various tendencies. This done, we have only to add the conditions common to all its phenomena, and, those appropriate to each place and rank, in the scale of ascent, and then proceed to determine the primary and constitutive forms, i.e. the elementary powers in which this tendency realizes itself under different degrees and conditions.[4]

What is Life? Were such a question proposed, we should be tempted to answer, what is not Life that really is? Our reason convinces us that the quantities of things, taken abstractedly as quantity, exist only in the relations they bear to the percipient; in plainer words, they exist only in our minds, ut quorum esse est percipi. For if the definite quantities have a ground, and therefore a reality, in the external world, and independent of the mind that perceives them, this ground is ipso facto a quality; the very etymon of this world showing that a quality, not taken in its own nature but in relation to another thing, is to be defined causa sufficiens, entia, de quibus loquimur; esse talia, qualia sunt. Either the quantities perceived exist only in the perception, or they have likewise a real existence. In the former case, the quality (the word is here used in an active sense) that determines them belongs to Life, per ipsam hypothesin; and in the other case, since by the agreement of all parties Life may exist in other forms than those of consciousness, or even of sensibility, the onus probandi falls on those who assert of any quality that it is not Life. For the analogy of all that we know is clearly in favour of the contrary supposition, and if a man would analyse the meaning of his own words, and carefully distinguish his perceptions and sensations from the external cause exciting them, and at the same time from the quantity or superficies under which that cause is acting, he would instantly find himself, if we mistake not, involuntarily identifying the ideas of Quality and Life. Life, it is admitted on all hands, does not necessarily imply consciousness or sensibility; and we, for our parts, cannot see that the irritability which metals manifest to galvanism, can be more remote from that which may be supposed to exist in the tribe of lichens, or in the helvellæ, pezizee, &c., than the latter is from the phenomena of excitability in the human body, whatever name it may be called by, or in whatever way it may modify itself.[5] That the mere act of growth does not constitute the idea of Life, or the absence of that act exclude it, we have a proof in every egg before it is placed under the hen, and in every grain of corn before it is put into the soil. All that could be deduced by fair reasoning would amount to this only, that the life of metals, as the power which effects and determines their comparative cohesion, ductility, &c., was yet lower on the scale than the Life which produces the first attempts of organization, in the almost shapeless tremella, or in such fungi as grow in the dark recesses of the mine.

  1. But still less would I avail myself of its acknowledged inappropriateness to the purposes of physiology, in order to cast a self-complacent sneer on the soul itself, and on all who believe in its existence. First, because in my opinion it would be impertinent; secondly, because it would be imprudent and injurious to the character of my profession; and, lastly, because it would argue an irreverence to the feelings of mankind, which I deem scarcely compatible with a good heart, and a degree of arrogance and presumption which I have never found, except in company with a corrupt taste and a shallow capacity.
  2. Vide Lawrence's Lecture.
  3. Joh. Bapt. a Vico, Neapol. Reg. eloq. Professor, de antiquissima Itallorum sapientia ex lingua Latina originibus aruendâ: libri tres. Neap., 1710.
  4. The object I have proposed to myself, and wherein its distinction exists, may be thus illustrated. A complex machine is presented to the common view, the moving power of which is hidden. Of those who are studying and examining it, one man fixes his attention on some one application of that power, on certain effects produced by that particular application, and on a certain part of the structure evidently appropriated to the production of these effects, neither the one or other of which he had discovered in a neighbouring machine, which he at the same time asserts to be quite distinct from the former, and to be moved by a power altogether different, though many of the works and operations are, he admits, common to both machines. In this supposed peculiarity he places the essential character of the former machine, and defines it by the presence of that which is, or which he supposes to be, absent in the latter. Supposing that a stranger to both were about to visit the two machines, this peculiarity would be so far useful as that it might enable him to distinguish the one from the other, and thus to look in the proper place for whatever else he had heard remarkable concerning either; not that he or his informant would understand the machine any better or otherwise, than the common character of a whole class in the nomenclature of botany would enable a person to understand all, or any one of the plants contained in that class. But if, on the other hand, the machine in question were such as no man was a stranger to, if even the supposed peculiarity, either by its effects, or by the construction of that portion of the works which produced them, were equally well known to all men, in this case we can conceive no use at all of such a definition; for at the best it could only be admitted as a definition for the purposes of nomenclature, which never adds to knowledge, although it may often facilitate its communication. But in this instance it would be nomenclature misplaced, and without an object. Such appears to me to be the case with all those definitions which place the essence of Life in nutrition, contractility, &c. As the second instance, I will take the inventor and maker of the machine himself, who knows its moving power, or perhaps himself constitutes it, who is, as it were, the soul of the work, and in whose mind all its parts, with all their bearings and relations, had pre-existed long before the machine itself had been put together. In him therefore there would reside, what it would be presumption to attempt to acquire, or to pretend to communicate, the most perfect insight not only of the machine itself, and of all its various operations, but of its ultimate principle and its essential causes. The mysterious ground, the efficient causes of vitality, and whether different lives differ absolutely or only in degree, He alone can know who not only said, "Let the earth bring forth the living creature, the beast of the earth after his kind, and it was so;" but who said, "Let us make man in our image, who himself breathed into his nostrils the breath of Life, and man became a living soul.
    The third case which I would apply to my own attempt would be that of the inquirer, who, presuming to know nothing of the power that moves the whole machine, takes those parts of it which are presented to his view, seeks to reduce its various movements to as few and simple laws of motion as possible, and out of their separate and conjoint action proceeds to explain and appropriate the structure and relative positions of the works. In obedience to the canon,—"Principia non esse multiplicanda præter summam necessitatem cui suffragamur non ideo quia causalem in mundo unitatem vel ratione vel experientiâ perspiciamus, sed illam ipsam indagamus impulsu intellectûs, qui tantundem sibi in explicatione phænomenorum profecisse videtur quantum ab codem principio ad plurima rationata descendere ipsi concessum est."
  5. The arborescent forms on a frosty morning, to be seen on the window and pavement, must have some relation to the more perfect forms developed in the vegetable world.