M/oNK AND HYDROGEN PEROXIDE DA LT< >.Vs LAW 215 



The essence of the atomic theory is that matter is supposed to con- 

 sist of an agglomeration of small and indivisible parts atoms which do 

 not fill up the whole space occupied by a substance, but stand apart 

 from each other, as the sun, planets, and stars do not fill up the whole 

 space of the universe, but are at a distance from each other. The form and 

 properties of substances are determined by the position of their atoms in 

 space and by their state of movement, while the phenomena accomplished 

 by substances are understood as redistributions of the relative positions 

 of atoms and changes in their movement. The atomic representation of 

 matter arose in very ancient times, 31 and up to recent times was at strife 

 with the dynamical hypothesis, which considers matter as only a mani- 

 festation of forces. At the present time, however, the majority of 

 scientific men uphold the atomic hypothesis, although the present con- 

 ception of an atom is quite different from that of the ancient 



which was impossible so long as definite compounds were separated from indefinite by a 

 sharp line of demarcation. 



51 Leucippus, Democritus, and especially Luoretius, in the classical ages, repre- 

 sented matter as made up of atoms that is, of parts incapable of further division. The 

 geometrical impossibility of such an admission, as well as the conclusions which were 

 deduced by the ancient atomists from their fundamental propositions, prevented other 

 philosophers from following them, and the atomic doctrine, like very many others, lived, 

 without being ratified by fact, in the imaginations of its followers. Between the present 

 atomic theory and the doctrine of the above-named ancient philosophers there is naturally 

 a remote historical connection, as between the doctrine of Pythagoras and Copernicus, 

 but they are essentially profoundly different. For us the atom is indivisible, not in 

 the geometrical abstract sense, but only in a physical and chemical sense. It would be 

 better to call the atoms indivisible individuals. The Greek atom = the Latin individual, 

 according to both the sum and sense of the words, but historically these two words are 

 endowed with a different meaning. The individual is mechanically and geometrically 

 divisible, but only indivisible in a definite sense. The earth, the sun, a man or fly 

 are individuals, although geometrically divisible. Thus the atoms of contemporary 

 science, indivisible in a physico-chemical sense, form those units which are concerned in 

 the investigation of the natural phenomena of matter, just as a man is an indivisible unit in 

 the investigation of social relations, or as the stars, planets, and luminaries serve as units 

 in astronomy. The formation of the vortex hypothesis, in which, as we shall afterwards 

 see, atoms are entire whirls mechanically complex, although physico-chemically indivisible, 

 already shows that the scientific men of our time in holding to the atomic theory have 

 only borrowed the word and form from the ancient philosophers, and not the essence of 

 their atomic doctrine. It is erroneous to imagine that the contemporary conceptions of 

 the atomists are nothing but the repetition of the metaphysical reasonings of the 

 ancients. As a geometrician in reasoning about curves represents them as formed of a 

 sum total of straight lines, because such a method enables him to analyse the subject 

 under investigation, so the scientific man applies the atomic theory as a method 

 of analysing the phenomena of nature. Naturally there are people now, as in ancient 

 times, and as there always will be, who apply reality to imagination, and therefore 

 there are to be found atomists of extreme views ; but it is not in their spirit that we 

 should acknowledge the great services rendered by the atomic doctrine to all science, 

 which, while it has been essentially independently developed, is, if it be desired to 

 reduce all ideas to the doctrines of the ancients, a union of the ancient dynamical and 

 atomic doctrines. 



