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 prejudiced persistence in an opinion and an unwillingness to revise it in the light of new facts or hypotheses; and "admit" implies the unwilling 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 consideration 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 consideration of new evidence.
There should never be, here or elsewhere, an appeal to the "authority" of some other investigator as a means of settling a doubtful question; 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 courteously: neither in spoken nor in printed reports should a sincere investigator allow himself to descend to disagreeable personalities, or permit himself to indulge in controversial polemics. His expressions regarding all other students of his subject, whether he agrees with them or not, should be such as shall promote personal intercourse when opportunity for it arises; for with whom can an investigator more advantageously 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