"The results of... prolonged studies are published in German under the title Gnosis und späntantiker Geist, of which the first volume appeared in 1934, the second—because of the circumstances of the times—only in 1954, and the third and concluding one is still to come. The present volume, while still retaining the point of view of the larger work and restating many of its arguments, is different in scope, in organization, and in literary intention. ...[T]his treatment ...strives to reach the general educated reader as well as the scholar. ...[I]n some respects the present volume goes beyond the earlier presentation: certain texts are more fully interpreted... and it has been possible to include new material of recent discovery. Inevitably... it does duplicate, with some rephrasing, certain parts of the German work."