"Those who wish to collect evidence about these matters (and it is quite reasonable that they should wish to do so) should turn to the earlier literature of the Society. If they meet our President, they can hear from her how many of the Great Ones she has seen on different occasions; and there are many of our members who will bear witness without hesitation that they have seen a Master. It may be that in meditation they have seen His face, and later have had definite proof that He is a real being. Much evidence may be found in Colonel Olcott' s Old Diary Leaves, and there is an interesting treatise called Do the Brothers Exist? written by Mr. A. O. Hume, a man who stood high in the Civil Service in India, and worked much with our late Vice-President, Mr. A. P. Sinnett."
January 1, 1970
https://en.wikiquote.org/wiki/The_Masters_and_the_Path