10 PRESIDENT’S ADDRESS. 
material brought to it by the spermatozoon, since it is possible to 
start the process of division of the ovum and the resulting formation 
of cells, and ultimately of all the tissues and organs—in short, to bring 
about the development of the whole body—if a simple chemical reagent 
is substituted for the male element in the process of fertilisation. 
Indeed, even a mechanical or electrical stimulus may suffice to start 
development. Kurz und gut, as the Germans say, vitalism 
The question as a working hypothesis has not only had its foundations 
of vitalism undermined, but most of the superstructure has toppled 
and vital , ; 4 : 3 : 
force. over, and if any difficulties of explanation still persist, we 
are justified in assuming that the cause is to be found in 
our imperfect knowledge of the constitution and working of living 
material. At the best vitalism explains nothing, and the term ‘ vital 
force’ is an expression of ignorance which can bring us no further 
along the path of knowledge. Nor is the problem in any way advanced 
by substituting for the term ‘ vitalism ’ ‘ neo-vitalism,’ and for ‘ vital 
force ’ ‘ biotic energy.’* ‘ New presbyter is but old priest writ large.’ 
Further, in its chemical composition we are no longer compelled 
to consider living substance as possessing infinite complexity, as was 
thought to be the case when chemists first began to break 
The possi- up the proteins of the body into their simpler con- 
wouniaia oF stituents. The researches of Miescher, which have been 
living matter. continued and elaborated by Kossel and his pupils, have 
acquainted us with the fact that a body so important for 
the nutritive and reproductive functions of the cell as the nucleus—which 
may be said indeed to represent the quintessence of cell-life—possesses 
a chemical constitution of no very great complexity; so that we may 
even hope some day to see the material which composes it prepared syn- 
thetically. And when we consider that the nucleus is not only itself 
formed of living substance, but is capable of causing other living sub- 
stance to be built up; is, in fact, the directing agent in all the principal 
chemical changes which take place within the living cell, it must be 
admitted that we are a long step forward in our knowledge of the chemical . 
basis of life. That it is the form of nuclear matter rather than its 
chemical and molecular structure which is the important factor in 
nuclear activity cannot be supposed. The form of nuclei, as every 
microscopist knows, varies infinitely, and there are numerous living 
organisms in which the nuclear matter is without form, appearing simply 
as granules distributed in the protoplasm. Not that the form assumed 
and the transformations undergone by the nucleus are without import- 
* B. Moore, in Recent Advances in Physiology, 1906; Moore and Roaf, ibid. ; 
and Further Advances in Physiology, 1909. Moore lays especial stress on the 
transformations of energy which occur in protoplasm. See on the question of 
vitalism Gley (Revue Scientifique, 1911) and 1)’Arcy Thompson (Address to 
Section D at Portsmouth, 1911). 
