PHYSIOLOGICAL KESEARCH AND 

 PHYSIOLOGICAL REASONING. 



We propose in this chapter to examine into the methods 

 employed in physiologcial investigation and teaching, and the 

 character of conclusions arrived at by physiologists as depend- 

 ent on a certain method of reasoning. 



The first step toward a legitimate conclusion in any one of 

 the inductive sciences to which physiology belongs is the col- 

 lection of facts which are to constitute the foundation on 

 which the inference is to be based. If there be any error in 

 these, a correct conclusion can not be drawn by any reliable 

 logical process. On the other hand, facts may abound in thou- 

 sands and yet the correct conclusion never be reached, because 

 the method of interpretation is faulty, which is equivalent to 

 saying that the process of inference is either incomplete or in- 

 correct. The conclusions of the ancients in regard to nature 

 were usually faulty from errors in both these directions ; they 

 neither had the requisite facts, nor did they correctly interpret 

 those with which they were conversant. 



Let us first examine into the methods employed by modern 

 physiologists, and determine in how far they are reliable. First, 

 there is the method of dived observation, in which no appara- 

 tus whatever or only the simplest kind is employed ; thus, the 

 student may count his own respirations, feel his own heart- 

 beats, count his pulse, and do a very great deal more that will 

 be pointed out hereafter ; or he may examine in like manner an- 

 other fellow-being or one of the lower animals. This method 

 is simple, easy of application, and is that usually employed by 

 the physician even at the present day, especially in private 

 practice. The value of the results obviously depends on the 

 reliability of the observer in two respects : First, as to the ac- 

 curacy, extent, and delicacy of his perceptions ; and, secondly, 

 on the inferences based on these sense-observations. Much 



