THE THEORY OF IMMUNITY 129 



supposition that life itself is the result of giant molecules. 

 It is, of course, wrong to infer that particular statements 

 are not true if rightly interpreted. "Antigens" certainly 

 produce specific " antibodies " as definite responses to the 

 chemical nature of the " antigen " ; but there is no reason 

 why this should not have been expressed in terms imply- 

 ing that any foreign or hostile elements introduced into an 

 organism tended to produce definite reactions of a pro- 

 tective nature. To invent or to lead to the invention of a 

 jargon containing such words as haptophore, ergophore, 

 complementophilogen, amboceptors, agglutinins, precipi- 

 tins, bacteriolysins, opsonins, syntoxoid, and so on, which 

 again bred other equally futile words of the same kind, 

 was but to stultify real explanation, and to cloud percep- 

 tion of the actual facts. When all this was hung upon the 

 giant molecule, a mere guess of Verworn's, the structure 

 naturally enough came to the ground. But, though the 

 whole theory of side-chains, except so far as they are 

 mere chemical phenomena, has been discredited, there are 

 yet able bacteriologists who continue to teach it as if Ehrlich 

 were accepted gospel. On my inquiring why they did so, 

 when they knew that the theory was no longer held by any 

 physiologist, two or three well-known men replied that it 

 was useful to students as a framework on which to hang 

 facts. To this it might be objected that, though a hat-rack 

 is useful to hang hats on, yet it is not the place to hang 

 hundredweights, and that when the hat-rack has the 

 additional disadvantage of being an imaginary one, there 

 will be more than common difficulties in the way of useful 

 arrangement. A compound may, perhaps, be cleared of 

 cobras by a mongoose ; but no competent zoologist will 

 employ the " imaginary mongoose " of fable at the task. 

 To teach what is not true merely as mnemonics is to 

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