2 THE POPULAR SCIENCE MONTHLY. 



child in the State knew that pitch was a " thick, black, sticky substance 

 obtained by boiling down tar," and not only that, but he and the great- 

 er part of those present would feel as though their attendance had been 

 obtained by false pretenses, and that the money they had paid for ad- 

 mission should be returned to them ? 



Or, if I should go out among the sturdy farmers of Northampton 

 County and gather them together to hear a lecture on "ducks," and 

 should confine my remarks to pets and darlings of the female part of 

 the human species, is it not very certain that though the young agri- 

 culturists in search of Avives would listen with eagerness to what I 

 had to say (and it would be interesting, I think), the more sedate would 

 feel as though I had played them a trick ? Neither the young nor the 

 old would have got what they came for, and yet there would be am- 

 ple authority for the meaning given to the word. 



And when I come before an educated assemblage such as this, com- 

 posed to a great extent of persons of both sexes, who have been in the 

 habit of thinking deeply on subjects of vast importance, and who have 

 formed clear ideas of what meanings are to be given to the words 

 they meet in their studies or use in their conversation, it is indispen- 

 sable that if I wish to make myself understood and to speak with that 

 force 60 essential in obtaining assent, I should do all in my power to 

 avoid ambiguity of signification. 



It would be very easy to bring before you many subjects in regard 

 to which you have your own ideas, formed after much study and re- 

 flection, and to which, therefore, you would have a right to cling, 

 and I should be obliged to start out by attempting to defifle accurately 

 the terms to be employed. I doubt, however, if it would be possible 

 to select one in which such a course would be more necessary than in 

 that of which I am to speak to-day. The word " mind " is a little 

 one, but it means a great deal, and if we strive for accuracy, as of 

 course we should do, it means a great many different things. In fact, 

 it is probable that, were I to send a canvasser among you, I should 

 receive a hundred different explanations of the term, and nowhere 

 would the variations be more numerous or more transcendental than 

 among the eminent gentlemen — president, professors, and trustees — 

 who constitute the governing body of this university ; for I think I 

 have observed that, the higher we go in mental development, the more 

 numerous and refined are the differences as to what the mind is. No 

 two metaphysicians ever yet exactly agreed in regard to the significa- 

 tion to be attached to the word mind. 



But, before explaining to you my understanding of the term, it is 

 necessary, in order to avoid all ground for misconception, to tell you 

 what I do not mean. I do not mean the soul, although it and the mind 

 are by a large and influential class of philosophers regarded as consti- 

 tuting one essence — as being, in fact, identical. With it, however, I 

 conceive that we have nothing to do, so far as science goes. Its very 



