are the great crucial points on which we may take our stand. I thank the 
meeting very much for the kind attention it has given to my paper. 
The meeting was then adjourned. 
PROFESSOR VIRCHOW ON EVOLUTION. 
The following speech was made by Professor Virchow, during the Edin- 
burgh University Tercentenary, 1884 :— 
“T should have wished to speak to you in your own language, but as I only 
received the invitation to this meeting on arriving in London, it was impos- 
sible for me to prepare a good address ; therefore I beg to be excused if 
I make my speech in German. [Professor Virchow then proceeded with 
his speech in German, of which the following isa translation.] In considering 
what to say that might be of interest to a group of students, 1 remembered 
that I would be speaking not only to Scotland, but to the whole English- 
speaking world. I knew that great subjects were discussed in your university, 
in the wide range of which the teachings of this school were largely in 
accordance with my own. Among the matters which have a common 
interest for us, I am in such cordial sympathy with you that there is only one 
topic on which there may seem to have been some disturbance in the happy 
relations which subsist between us. You will allow me to speak to you on 
the position which Iam supposed to have taken up towards the teachings of 
Darwin. The opinions which I expressed have, in some English publications, 
been much misunderstood. I never was hostile to Darwin, never have said 
that Darwinism was a scientific impossibility. But at that time, when I pro- 
nounced my opinion on Darwinism at the Association of German Naturalists 
at Munich, I was convinced, and still am, that the development which it 
had taken in Germany was extreme and arbitrary. Allow me to state to 
you the reasons on which I founded my opinions. Firstly, Darwinism was 
interpreted in Germany as including the question of the first origin in life, 
not merely its manner of propagation. Whoever investigates the subject of 
development, comes upon the question of the creation of life. This was 
not a new question. It is the old generatio equivoca, or Epigenesis. Does 
life arise from a peculiar arrangement of inorganic atoms under certain 
conditions? We can imagine oxygen, hydrogen, carbon, and nitrogen 
coming together to form albumen, and that out of the albumen there was 
produced a living cell. All this is possible; but the highest possibility is 
only a speculation, and cannot be admitted as the basis of a doctrine. In 
science it is not hypotheses that decide, but facts ; we arrive at truth only 
by investigation and experiment. I need not say that this demand of 
science for proof, instead of speculation, was long ago made in England. 
Ever since the time of Bacon it has had a home amongst you. We may con- 
cede that generatio equivoca is a logical possibility. But it is important for 
you students always to bear in mind the great distinctions between the con- 
struction of logical possibilities and their application in practical life. If you 
try to shape your conduct simply according to logical possibilities, you will 
often find yourself coming into violent conflict with the stern facts of 
existence. Let me give you an illustration. In recent times, the fact of the 
presence of minute organisms giving rise to important processes has been 
recognised, not only in medicine, but in connexion with agriculture, and 
various industries. It was of the utmost importance to determine whether 
these organisms were originated de novo in the decomposing bodies, or were 
produced by similar pre-existing organisms, and introduced from without. 
A century ago it was possible to admit the spontaneous generation of 
microbia. But here sits M. Pasteur, the man who has demonstrated by 
means of direct experiment that, in spite of all logical possibility, all known 
