2 3 o THE POPULAR SCIENCE MONTHLY 



another; he must assume the impartial attitude of a just judge rather 

 than the partisan attitude of a retained lawyer. He must not advocate 

 any particular theory, or urge any special conclusion upon his hearers; 

 it is for the facts themselves to advocate the acceptance of whatever 

 hypothesis best accounts for them; it is for the consequences that 

 successfully confront the facts to urge the acceptance of the hypothesis 

 from which they were deduced. The speaker should avoid the use of 

 such words as maintain and admit; for "maintain" implies a prej- 

 udiced persistence in an opinion and an unwillingness to revise it in 

 the light of new facts or hypotheses ; and " admit " implies the unwil- 

 ling acceptance of facts or deductions which ought to be accepted 

 willingly and hospitably, if they are at all pertinent to the problem in 

 hand. There is indeed much significance here in the choice of words 

 and phrases. A speaker may fairly urge upon his hearers the considera- 

 tion but not the acceptance of a certain hypothesis; he may properly 

 insist upon the importance of thorough work, but not upon the belief in 

 his conclusions; he may hold that critical revision of all steps in 

 theoretical work is essential to success, but he ought not to hold his 

 theoretical results as beyond revision, however confident he may be of 

 their correctness. His words show his state of mind in all these 

 respects: hence the importance of selecting them carefully. If a 

 speaker says : " Even the latest researches of other geographers have not 

 driven me from the position which I have maintained from the first," 

 his hearers may be excused if they regard him as not open to the con- 

 sideration of new evidence. 



There should never be, here or elsewhere, an appeal to the " author- 

 ity " of some other investigator as a means of settling a doubtful ques- 

 tion ; the appeal should be made only to the evidence that has convinced 

 the other investigator. If there be occasion to dissent from the opinion 

 of other investigators, the dissent should always be expressed courte- 

 ously : neither in spoken nor in printed reports should a sincere investi- 

 gator allow himself to descend to disagreeable personalities, or permit 

 himself to indulge in controversial polemics. His expressions regard- 

 ing all other students of his subject, whether he agrees with them or 

 not, should be such as shall promote personal intercourse when oppor- 

 tunity for it arises; for with whom can an investigator more advan- 

 tageously associate than with those who pursue studies like his own, 

 particularly if their conclusions differ from the ones that he has reached. 



The analytical method of presentation, perhaps more than any other, 

 demands of the speaker an appreciation of the dramatic element that 

 enters, in greater or less degree, in every report made by an investigator 

 to an audience; but the speaker's part should be that of stage manager 

 rather than that of actor. He should stand, as it were, to one side, 

 withdrawing his own personality so as the more effectively to bring 

 forward the facts, hypotheses and other members of his troupe; each 



