The clear conception of the Open Conspiracy is a considerable but necessary intellectual effort. A group of historical, biological and economic ideas and interpretations has to be assimilated and they are not by any means simple and obvious ideas. And in addition--and what is perhaps the more difficult part--many prevalent habits of mind and current assumptions have to be got rid of. The conception of the Open Conspiracy involves, for example, a sceptical and destructive criticism of personal-immortality religions and also of the sacred formulæ of communism. It can work, and may go far in certain ways, with Christians or Communists, but it cannot incorporate them so long as they are Christians or Communists. Vague goodwill for mankind, or for progress, and adhesions based on some partial approval of its spirit, its methods or its objective, are of no real value to an enterprise so huge in its ultimate intentions. For the furtherance of its aims, the Open Conspiracy may work in alliance with all sorts of movements and people, but to take them into its own essential substance is an altogether different matter. Propaganda and education are seed-sowing and only in revivalist religion is an immediate, a simultaneous reaping attempted with the sowing of the seed. The general run of people are more eager to do than to understand, and from the beginning of its first overt activities the Open Conspiracy will have to deal with the friendly advances of those who will want to share in its effort without any proper assimilation of the ideas that promote it. This will be another reason for projecting its practical activities into the form of _ad hoc_ associations, into which outsiders with different or undeveloped religious, political, social and philosophical views may come without penetrating as permanent members into the actual groups, and it will also justify the helpful participation of the Open Conspiracy groups in definitely restricted movements which attend only to a portion of its programme. But many of those who first come into touch with the Open Conspiracy simply as helpers and allies will no doubt go on to a careful study of its general concepts and so to complete participation.