"Ignorant, indeed, of the nature of Keely's work must those men be who accuse him of "abandoning his base" or "principle," each time that he discovers his mistakes: using them as stepping-stones to approach nearer and still nearer to his goal. Reproaching him, even, for keeping his own counsel, until certainly of success rendered it prudent for him to make known that he had changed his field of experiment from positive attraction to negative attraction." [The Key to the Problems. - Keelys Secrets]