From the author, Peter V. Ross - On September 23, 1933, I lectured at the Chicago World’s Fair. Two or three years later there came into circulation typewritten reports of the lecture under the caption “The Cornerstone of Christian Science Practice.” Evidently someone took notes of this discourse, transcribed them, and set the document afloat. I have no information just how this was done or who participated.

But typewritten copies have multiplied to the extent that this lecture has gone round the world. Scarcely a week goes by that someone does not express to me his keen appreciation. Hundreds have reported definite healings from their study of the manuscript.

So dynamic has been the effect of the lecture, that, in presenting it here, I have not dared do more, in the way of revision, than to correct some of the glaring errors in English which have crept in from time to time in the course of copying. The document furnishes a striking example of the fact that the spirit of a discourse, not the words, produces the effect.