54 PLANTS AND ANIMALS NOT MACHINES, 



matter, and that the waste of energy in the working of every 

 known machine is as remarkable as the wonderful economy 

 of material and little loss of energy by which every part of 

 the "living machine" in a healthy state is characterised. 

 Nevertheless he persists in speaking of muscular contraction 

 as if there was nothing more to be learnt about it, and 

 quietly places it in the category of machine actions, 

 although he knows nothing whatever of the arrangement of 

 the active particles, " molecular machinery" of the so-called 

 muscular machine. Most of the pretentious phrases and 

 prodigious assertions of the new schoolmen are but con- 

 tributions to the philosophy of assumption. People may 

 be encouraged to fancy that they know a great deal more 

 than they really do. Progress may be hopelessly retarded, 

 and not only will a dislike to the particular kind of teach- 

 ing by which they have been misled be excited, but it is to 

 be feared people will be led to distrust scientific information 

 of every kind. 



Although plants and animals have been oftentimes com- 

 pared with machines, no one has yet taught exactly in what 

 particulars any plant or animal is like any machine. For 

 my part, I cannot discover the slightest resemblance in 

 origin, form, composition, or mode of action. I have looked 

 over and over again at the matter of the living plant and 

 animal in which or by which the wonderful changes charac- 

 teristic of it are effected in health and disease, but I have 

 seen nothing save a little transparent, structureless, colour- 

 less, semi-fluid stuff. I even see this move. While under 

 my observation various substances of complex chemical 

 composition may be formed through its agency, but the 

 highest magnifying powers do not enable me to form any 



