But I am content to say for the present that from the point of view of strict science it is not yet possible to give any positive answer to these questions; that they must await the progress of discovery. It becomes a question of some interest, therefore, how it is possible for Professor Haeckel and for others of his school to have arrived at the idea not only that a scientific answer can be given, but that already it has been given, and that they know distinctly what it is.
Note on the Word "Life."
Until a term is accurately defined, and even afterwards for some purposes, it is permissible to use a word of large significance in more than one sense. Thus the word "light" may be considered a psychological term, denoting a certain sensation, or a physiological term, signifying the stimulus of certain specialised nerve-endings, or a physical term, expressing briefly an electromagnetic wave-disturbance in the ether. I am using the word "life" in a quite general sense, as is obvious, for if it be limited to certain metabolic processes in protoplasm—which is the narrowest of its legitimate meanings—what I have said about its possible existence apart from matter would be absurd. It may be convenient to employ the word "vitality" for this limited sense; but so far as I know, there is no general consensus of usage, and the context must suffice to show a friendly reader the connotation intended.
CHAPTER III
THE DEVELOPMENT OF LIFE
This leads me to the second main thesis or central scientific doctrine of Professor Haeckel's treatise, the biological one; and it is this which I shall now proceed to illustrate by further quotations, viz., the connection as he conceives it between life and matter.
His view is that life has arisen from inorganic matter without antecedent life. The experimental facts of biogenesis he discards in favour of a hypothetical and at present undiscovered kind of spontaneous generation. He assumes that the chemico-physical properties of carbon confer so peculiar a power on its albuminoid compounds that they develop into living protoplasm. He says that he formulated this view thirty-three years ago, and that no better monistic theory has arisen to replace it, while to reject some form of spontaneous generation is to admit a miracle:—
"The hypothesis of spontaneous generation, and the allied carbon-theory (viz., that 'carbon ... may be considered the chemical basis of life,' p. 2) are of great importance in deciding the long-standing conflict between the teleological (dualistic) and the mechanical (monistic) interpretation of phenomena" (p. 91).
But it can hardly be maintained that a "hypothesis" is able to "decide" any dispute. (See, however, Chapter VI.)
An unscientific reader could hardly imagine that the apparently detailed account given in the next sentence of the automatic origin of life, as it may have arisen on other planes, and as it must have arisen on this, is of the nature of hypothesis:—