vm, J C{p Stimtific &ap*rfa 0f f oaitibiam. 169 



the historical development of the sciences, and -their 

 position in the Comtean hierarchy, in his essay on the 

 "Genesis of Science," that I shall not waste time in 

 repeating his refutation, 



A third proposition in support of the Comtean classi- 

 fication of the sciences stands as follows: 



"En troisieme lieu cette classification prese,te la propriety tres- 

 remarquable de marquer exactement la perfection relative des diffe- 

 rentes sciences, laquelle consiste essentiellement dans le degre de 

 precision des connaissances et dans leur co-ordination plus ou moins 

 intime." 1 



I am quite unable to understand the distinction which 

 M. Comte endeavours to draw in this passage in spite 

 of his amplifications further on. Every science must 

 consist of precise knowledge, and that knowledge must 

 be co-ordinated into general proportions, or it is not 

 science. When M. Comte, in exemplification of the 

 statement I have cited, says that "les phdnomenes 

 organiques ne comportent qu'une ^tude a la fois moins 

 exacte et moins syst^matique que les phenomenes 

 corps bruts," I am at a loss to comprehend what he 

 means. If I affirm that "when a motor nerve is irri- 

 tated, the muscle connected with it becomes simultane- 

 ously shorter and thicker, without changing its volume/' 

 it appears to me that the statement is as precise or exact 

 (and not merely as true) as that of the physicist who 

 should say, that "when a piece of iron is heated, it 

 becomes simultaneously longer and thicker and increases 

 in volume ;" nor can I discover any difference, in point 

 of precision, between the statement of the morphological 

 law that "animals which suckle their young have two 

 occipital condyles," and the enunciation of the physical 

 law that "water subjected to electrolysis is replaced by 

 an equal weight of the gases, oxygen and hydrogen." 



1 "Philosophie Positive i p. 78. 



