Problems of Life and Mind. Second series, George Henry Lewes [e book reading free TXT] 📗

Force nor Bioplasm covers the whole ground. For the former there is no better evidence than our ignorance of the real synthesis; for the latter the evidence is positive in its nature, but its interpretation is questionable. Dr. Beale selects as the germinal matter those portions of tissue which are susceptible of being deeply stained by the carmine solution, the formed material being only stained in a faint degree; the nucleus and nucleolus are the portions of germinal matter which are most deeply stained; and hence he concludes that the older the matter the fainter will be its coloration. There is no dispute as to the value of the staining process, invented by Gerlach, for the discrimination of chemically different parts of a tissue; and Dr. Beale has made excellent use of it in his researches.28 But I altogether dispute the conclusion that the staining process reveals the parts which are exclusively vital; and for this reason: it depends solely on the acid reaction of those parts; and we cannot divorce the acid from the alkaline agencies, both being indispensable. Nay, it has been proved that in the living animal no organized substance can be stained. Lord Godolphin Osborne first discovered, in 1856, that the protoplasm of growing wheat was susceptible of coloration;29 but Gerlach, in 1858, found that this never took place in the animal during life. He kept tadpoles and intestinal worms for weeks in colored fluids, without a single spot becoming stained; although no sooner did these animals die than the staining began. Nor even when he injected the colored fluids under the skin and into the stomach, was the slightest coloration produced.30

To Gerlach’s testimony may be added that of Stein, who, in his magnificent work on Infusoria, says that not only has no foreign substance ever been found in the protoplasm of the Opalina, but in the Acineta, and all the embryos of the higher Infusoria known to him, he has been unable to color the living substance.31 This resistance of the living protoplasm is surely a serious objection to the hypothesis that only those parts of the dead organism which are stained were the truly vital parts. Ranke sums up the results of his experiments thus: “They all show that the living cell resists the imbibition of every substance which it cannot assimilate. It is precisely the impossibility of staining the cell that proves this conclusively, since every particle of carmine absorbed would have revealed its presence.”

It is not to be supposed that Dr. Beale was unacquainted with Gerlach’s experiments. He has at any rate so far qualified the statement of his hypothesis as to admit that it is only after death that the germinal matter is stained. “The living matter” (he says, How to Work with the Microscope, p. 107) “possesses an acid reaction, or to speak more correctly, an acid reaction is always developed immediately after its death.” Now, since this acid reaction only presents itself after death, and it is this which is revealed by the carmine, we have no right to conclude that the carmine singles out the vital parts. Every one knows that the living muscle and nerve, when in repose, present an alkaline or faintly neutral reaction, and after excitation this is changed into an acid reaction, which increases with the exhaustion of the tissue. In strict logic, therefore—if we could logically apply such a test—it is the unstained parts that ought to be called vital. But, in truth, alkalinity and acidity are equally indispensable.

78. The main object of my bringing this question forward was to illustrate the danger of being misled by analysis: a danger we shall see to be very serious in psychological inquiries. The aid derived from analysis need never be undervalued; all that we have to bear in mind is that it is only a logical artifice, and that our real explanation must always be synthetic. Because of the tendency to rely on analysis there has been an imperfect discrimination of the profound difference between

ORGANISMS AND MACHINES;

and while on the one hand the legitimate striving of the biologist to display the mechanism of organic actions has been denounced by a certain school as Materialism and a hateful attempt to “rob Life of its mystery,” there has been on the other hand a misconception of this mechanism, as if its dependent actions were of the nature of machines, that is to say, as if organized mechanisms were strictly comparable with machines constructed of inorganic parts. No doubt the laws of Mechanics are the same in both, for these are abstract laws which take no account of concrete differences. But when elaborate parallels are drawn up between steam-engines and animal organisms, the coal consumed in the one likened to the food in the other, and the force evolved in the combustion in both being the same, there is a complete obliteration of all that specially distinguishes vital activity.

79. Between an organism and a machine there is the superficial resemblance that both have a complex structure, and are constructed of different and dependent parts. But underneath this resemblance there is a radical diversity.32 The arrangement of parts in the organism is more than a juxtaposition, it is a solidarity, arising from the fact of their being all differentiations from a common substance which is a special combination of the three classes of proximate principles. Thus they are not parts which have been put together, but which have been evolved, each out of a pre-existing part, and each co-operating in the very existence of the other. The machine is made of independent and primarily unrelated parts; its integrity depends on the continued preservation of the substance of each part; waste is here destruction. The organism is constituted by interdependent and primarily related parts; its integrity depends on the continued destruction and renovation of their substance; waste is a condition of vitality. The actions of the machine are subordinated; the actions of an organism are co-ordinated. The lever moves a wheel, and the wheel in moving liberates a spring, each transmitting a communicated impulse, but otherwise each acts independently—no slight modification in the structure or movement of the wheel will modify the structure or the movements of the lever, no alteration in the tension of the spring will affect the structure of the wheel. But in the organism all are parts of one sympathetic whole; each reacts on each; each is altered by the other. Not a nerve is stimulated, nor a muscle moved, but the entire organism is affected. A condensation here is the cause of a greater imbibition there. The injection of salt or sugar under the skin of the frog’s leg will produce cataract in its eye. The activity of a secreting cell in the ovary, or liver, alters the condition of the brain; the activity of the brain will check the secretion of a gland, or relax the sphincters of the bladder. When we observe the growth of horns, or the appearance of the beard, concomitant with the secretion of spermatic cells—and especially when we observe with these a surprising change in the physical and moral capabilities and tendencies of the organism—we understand how the remotest parts of this mechanism are bound together by one subtle yet all-powerful tie. Nothing of this is visible in a machine. In a machine the material is so far of secondary importance that it may be replaced by materials of various kinds: a pulley may be worked with a hempen cord, a silken cord, or an iron chain; a wheel may be wood, iron, copper, brass, or steel; the actions will in each case be similar. Not so the organic mechanism: the slightest variation, either in composition or intimate structure, will affect, and may frustrate the organic activity. It is only in the skeleton that the specific character of the materials may be changed; and here only in the substitution of one phosphate for another in the solid masonry.33

80. Another marked characteristic of the organism is that it has a connexus of actions, the simultaneous effect of a continuous evolution, appearing in stages and ages. And in the animal organism there is a consensus as well as a connexus, through which there is evolution of Mind; and in the Social Organism an evolution of Civilization. This consensus forms an intermediate stage through which the animal actions are sensitive as well as nutritive, and the nutritive are regulated by the sensitive. It is obvious that nothing like this is to be found in a machine; and we conclude, therefore, that any view of the organism which regards its mechanism without taking in these cardinal characteristics must be radically defective. We no more deny the existence of mechanical phenomena in denying that the organism is like a machine, than we deny the existence of chemical phenomena in denying that Vitality is chemical.