ILLUSTRATIONS OF THE LOGIC OF SCIENCE. 293 



occur, no matter how improbable they may be. What the habit is 

 depends on when and how it causes us to act. As for the when, every 

 stimulus to action is derived from perception; as for the how, every 

 purpose of action is to produce some sensible result. Thus, we come 

 down to what is tangible and practical, as the root of every real dis- 

 tinction of thought, no matter how subtile it may be ; and there is no 

 distinction of meaning so fine as to consist in anything but a possible 

 difference of practice. 



To see what this principle leads to, consider in the light of it such 

 a doctrine as that of transubstantiation. The Protestant churches 

 generally hold that the elements of the sacrament are flesh and blood 

 only in a tropical sense ; they nourish our souls as meat and the "juice 

 of it would our bodies. But the Catholics maintain that they are 

 literally just that ; although they possess all the sensible qualities of 

 wafer-cakes and diluted wine. But we can have no conception of 

 wine except what may enter into a belief, either 



1. That this, that, or the other, is wine ; or, 



2. That wine possesses certain properties. 



Such beliefs are nothing but self-notifications that we should, upon 

 occasion, act in regard to such things as we believe to be wine accord- 

 ing to the qualities which we believe wine to possess. The occasion 

 of such action would be some sensible perception, the motive of it to 

 produce some sensible result. Thus our action has exclusive reference 

 to what affects the senses, our habit has the same bearing as our ac- 

 tion, our belief the same as our habit, our conception the same as our 

 belief; and we can consequently mean nothing by wine but what has 

 certain effects, direct or indirect, upon our senses ; and to talk of 

 something as having all the sensible characters of wine, yet being in 

 reality blood, is senseless jargon. Now, it is not my object to pursue 

 the theological question ; and having used it as a logical example I 

 drop it, without caring to anticipate the theologian's reply. I only 

 desire to point out how impossible it is that we should have an 

 idea in our minds which relates to anything but conceived sensible 

 effects of things. Our idea of anything is our idea of its sensible 

 effects ; and if we fancy that we have any other we deceive ourselves, 

 and mistake a mere sensation accompanying the thought for a part of 

 the thought itself. It is absurd to say that thought has any meaning 

 unrelated to its only function. It is foolish for Catholics and Protes- 

 tants to fancy themselves in disagreement about the elements of the 

 sacrament, if they agree in regard to all their sensible effects, here or 

 hereafter. 



It appears, then, that the rule for attaining the third grade of 

 clearness of apprehension is as follows ; Consider what effects, which 

 might conceivably have practical bearings, we conceive the object of 

 our conception to have. Then, our conception of these effects is the 

 whole of our conception of the object. 



