THE VITAL PRINCIPLE. 25 



expressions from frittering away the great truth that, as there is but one 

 God in the universe, so there is but one spirit in man. 



On one of these terms, the vital principle, I may make a few remarks, 

 since, from being a mere expression of convenience, it has by de- The vital 

 grees risen among physicians and physiologists to the rank of P rmci P le - 

 designating an existing agent, by some regarded as of the same kind as 

 light, heat, electricity, or gravitation nay, even superior to them, since it 

 is its peculiar attribute to hold them all in check. Animated by this ex- 

 traordinary power, organic substances are supposed to withstand every 

 external influence, and to submit to physical agents only after this prin- 

 ciple has left them. Such a preposterous doctrine will not bear the 

 touch of exact science for a moment. It is only a relic of the old meta- 

 physical system of philosophizing, which accepted a name in lieu of an 

 explanation, which preferred the dogma of the horror of a vacuum to the 

 more simple but material view of the pressure of the air. By the aid of 

 this imaginary principle, complete physiological systems have been wov- 

 en, in which every act and every condition of the animal economy is spon- 

 taneously explained, and nothing remains for solution. But by the stu- 

 dent of nature, whose mind has been trained in positive science, the im- 

 posture is detected. He sees at a glance that this is not the style of the 

 Great Artist. The problems of organization are not to be solved by em- 

 pirical schemes ; they require the patient application of all importance of 

 the aids that can be furnished by all other branches of hu- 

 man knowledge, and even then the solution comes tardily, ology. 

 Yet there is no cause for us to adopt those quick but visionary specula- 

 tions, or to despair of giving the true explanation of all physiological 

 facts. Since it is given us to know our own existence, and be conscious 

 of our own individuality, we may rest assured that we have what is in 

 reality a far less wonderful power, the capacity of comprehending all the 

 conditions of our life. God has framed our understanding to grasp all 

 these things. For my own part, I have no sympathy with those who 

 say of this or that physiological problem, it is above our reason. My 

 faith in the power of the intellect of man is profound. Far from suppos- 

 ing that there are many things in the structure and functions of the body 

 which we can never comprehend, I believe there is nothing in it that we 

 shall not at last explain. Then, and not till then, will man be a perfect 

 monument of the wisdom and power of his Maker, a created being know- 

 ing his own existence, and capable of explaining it. In the application 

 of exact science to physiology, I look for the rise of that great and noble 

 practice of medicine which, in a future age, will rival in precision the me- 

 chanical engineering of my times. In it, too, are my hopes of the final 

 K extinction of empiricism. Even now this method is attended with results 

 rhich must commend it to every thoughtful mind, since it is connecting 



