In summary, then, to be an Objectivist means to accept, among other things, the assertion that there is an external reality, and that man’s mind, man’s reason, is an instrument adequate and appropriate to the investigation of that reality. But this assertion is meaningful only in the context of beliefs about the nature and origin of man’s mind which are consistent with that assertion. The dropping of that context renders the affirmation of confidence in man’s mind meaningless. Dr. Branden has written at length about the fallacy of the stolen concept, the attempt so frequently made by anti-rational philosophers to utilize a concept outside the rational framework which alone renders that concept meaningful. [01] Ladies and gentlemen, the atheist who, while remaining an atheist, undertakes to accept the fundamental principles of Objectivism, and to reason therefrom, provides us with a classic example, a textbook example, of the fallacy of the stolen concept.  

References
[Editor’s notes are in blue.]

* The title refers to Nathaniel Branden’s lecture “The Concept of God,” from his lecture series “The Basic Principles of Objectivism.” That lecture is fully transcribed in his book The Vision of Ayn Rand: The Basic Principles of Objectivism (Gilbert, Ariz.: Cobden Press, 2009), chapter 4. Partial and perhaps complete audios seem to be available throughout the Internet, especially here. See also R.A. Childs, “The Epistemological Basis of Anarchism,” Note 19.

[01] N. Branden, “The Stolen Concept,” 2/1/2, 4. [References of this form refer to The Objectivist Newsletter, so that volume 2, number 1 would be January 1963. After volume 4, the name of the publication was The Objectivist. The page numbers for the latter are those of the original format, not those in the bound volume.]