2/8 THE CELL-THEORY 



or, to use the language of the day, that the " vital forces " are molecular 

 forces. 



It will doubtless be said by many, But what guides these molecular 

 forces ? Some Cause, some Force, must rule the atoms and determine 

 their arrangement into cells and organs ; there must be something, call 

 it what you will — Archaeus, " Bildungs-trieb," " Vis Essentialis," Vital 

 Force, Cell-force — by whose energy the vital phenomena in each case 

 are what they are. 



We have but one answer to such inquiries : Physiology and 

 Ontology are two sciences which cannot be too carefully kept apart ; 

 there may be such entities as causes, powers, and forces, but they are 

 the subjects of the latter, and not of the former science, in which their 

 assumption has hitherto been a mere gaudy cloak for ignorance. For 

 us, physiology is but a branch of the humble philosophy of facts ; and 

 when it has ascertained the phenomena presented by living beings and 

 their order, its powers are exhausted. If cause, power, and force mean 

 anything but convenient names for the mode of association of facts, 

 physiology is powerless to reach them. It is satisfactory to reflect, 

 however, that in this comparatively limited sphere the inquiring mind 

 may }'et find much occupation. 



