24 Instinct. 



not to say our moral convictions, like the shock of 

 the suddenly stopping car to the body, for some 

 bold innovator to demolish as baseless or false, some 

 favorite definition — some good old form of speech 

 in which our thoughts had run as in the track of 

 truth. 



But this power of language has its use. When 

 truth has taken a particular formula of words for 

 its expression, the formula alone will often answer 

 our purpose ; and we can use it, as does the mathe- 

 matician his algebraic formulas, without the trouble 

 of verifying them in every operation. It be- 

 comes one then who enters upon any investigation 

 or discussion for the sake of truth, to guard himself 

 at every step, lest he be misled by old formulas or 

 by taking advantage of accepted formulas, cover 

 error with them, deceiving himself and perchance 

 those whom he attempts to instruct. If his object 

 is simply to carry a point, the more he can bring 

 his new doctrines under old forms of speech and 

 his errors into the formulas that custom has stamp- 

 ed with the sanction of truth, the better will he 

 succeed. 



There is at the present time much controversy 

 in the scientific world not only because men seem 

 determined to confine the Baconian philosophy to 

 matter alone, but because they insist upon using 

 the same formulas for very different elements in 

 the great circle of truth. The sine of ninety de- 

 grees is equal to radius, but the tangent of ninety 

 degrees is infinite, and any mathematician who af- 

 firms that they are equal simply because they are 



