302 



THE POPULAR SCIENCE MONTHLY.— SUPPLEMENT. 



apparent than in the history of evolution. The 

 question of the primal origin of organic beings, 

 a question which is at the basis of advanced Dar- 

 winism, is very ancient. We know not who was 

 the first to attempt a solution of it. But when 

 we quote the old popular theory, which teaches 

 that all possible living things, whether animals or 

 plants, may originate from a lump of clay — a 

 lumplet, as the case might be — we should at the 

 same time remember that the famous doctrine of 

 generalio cequivoca, or epigenesis, is closely allied 

 to it, and that it has been a common idea for 

 thousands of years. Now, with Darwinism the 

 doctrine of spontaneous generation has been 

 taken up again, nor can I deny that there is 

 something very alluring in the idea of thus 

 crowniug the theory of descent, and, after the 

 whole series of living forms has been constructed, 

 from the lowest of the protista up to the highest 

 human organism, of furthermore connecting this 

 long series with the inorganic world. All this is 

 in harmony with that tendency toward generaliza- 

 tion which is so characteristic of the human mind 

 that it has ever since the earliest times occupied 

 a place in the speculation of mankind. We do 

 unquestionably repugn against divorcing the or- 

 ganic world from the rest of the universe as some- 

 thing apart, and we incline rather to make the 

 union between them closer. In this sense it is 

 some satisfaction to be able to say that the group 

 of atoms known as Carbon & Co. — though rather 

 curt, the style is nevertheless correct enough, in- 

 asmuch as carbon is the main thing — that the firm 

 of Carbon & Co. once upon a time separated it- 

 self from ordinary carbon, and under special con- 

 ditions produced the first plastidule, and that it 

 still continues to do the same thing. But in the 

 face of this we have to state that all real scientific 

 knowledge has proceeded in the opposite direc- 

 tion. We date the beginning of our real knowl- 

 edge of the development of higher organisms from 

 the day when Harvey uttered the famous propo- 

 sition, Onine vivum ex ovo — every living being 

 comes from an egg. This proposition, as we now 

 know, is incorrect in its universality. We can 

 nowadays no longer regard it as fully established ; 

 indeed, we now know of a multitude of genera- 

 tions and propagations that take place without 

 ova. From the time of Harvey down to that of 

 our illustrious friend Von Siebold, who obtained 

 general recognition for the doctrine of partheno- 

 genesis, there has been established a whole series 

 of limitations which go to show that the expres- 

 sion Omne vivum ex ovo was as a general propo- 

 sition inexact. Nevertheless, it were the height 



of ingratitude not to recognize in Harvey's oppo- 

 sition to the old generalio cequivoca the greatest 

 advance that has been made by science in this 

 field. Later we became acquainted with a great 

 number of new forms of propagation in sundry 

 species of living beings — as direct segmentation, 

 gemmation, and alternate generation. All these 

 forms of generation, parthenogenesis included, 

 constitute the grounds upon which we have re- 

 jected all unitary systems of the generation of 

 organic individuals. Instead of a unitary scheme, 

 we have a number of different schemes ; and now 

 we have no one formula to explain once for all 

 how a new animal existence begins. 



Generatio cequivoca, however often attacked 

 and refuted, nevertheless confronts us continu- 

 ally. True it is, that not a single positive fa ct is 

 known proving that generatio cequivoca has ever 

 occurred ; that ever inorganic masses, for in- 

 stance, the firm of Carbon & Co., have spontane- 

 ously developed into an organic substance. Still 

 I admit that if we will form an idea how the first 

 organic being could have originated by itself, 

 nothing remains but to go back to spontaneous 

 generation. This is clear : if I will not accept a 

 theory of creation ; if I will not believe that there 

 was a special Creator who took up a lump of clay 

 and breathed into it the breath of life ; if I would 

 account for things in my own way, I must recur 

 to generatio cequivoca. Tertium non datur. Noth- 

 ing else remains if once we say, "I do not admit 

 creation, but I do want an explanation." If that 

 is your antecedent proposition, then you must 

 proceed to your consequent and say, " Ergo I ad- 

 mit generatio cequivoca.' 1 ' 1 But we have no actual 

 proof for it. Nobody has ever seen generatio 

 cequivoca occurring in reality, and every one who 

 maintained that he had seen it has been refuted, 

 not by theologians at all, but by naturalists. I 

 mention this, gentlemen, in order to let our im- 

 partiality appear in the right light, and this is 

 very necessary at times. We always have our 

 weapons in ourselves and about us, to fight against 

 that which is not fortified with proof. 



I therefore say that I must admit the theo- 

 retical justification of such a formula. Whoever 

 will have a formula, whoever says, " I absolutely 

 want a formula, I wish to be perfectly at one 

 with myself, I must have a coherent conception 

 of the universe," must either admit generatio 

 cequivoca or creation ; there is no other alterna- 

 tive. If we want to be outspoken we may in- 

 deed own that naturalists have a slight predilec- 

 tion for gcnci-atio cequivoca. It would be very 

 beautiful if it could be proved. 



