Van Vogt's work is essentially SF adventure whose protagonists frequently have some superhuman mental powers, derived through mutation or special training. It is this characteristic of wish-fulfillment that has made his stories so popular among adolescent readers. The supreme example of this is van Vogt's first novel, Slan, which follows the growing up a mutant with telepathic powers and enhanced intelligence (a slan), who grows to realise the vital role he will play in society. Nevertheless the stories are laced with ideas atypical and more thoroughly detailed than those used by more simplistic Golden Age writers such as E.E. Smith. The Voyage of the Space Beagle has many elements of traditional Space Opera, but is interesting for its examination of shipboard politics, and a pseudo-science similar to the quasi-philosophical movement of General Semantics that van Vogt uses in his most important work, The World of Null-A, and its sequel, The Pawns of Null-A.
Gilbert Gosseyn (`go sane'), the protagonist of The World of Null-A, General Semanticist extrordinaire, first finds his memory to be a fabrication, then that he has an extra brain with unknown powers, and then that he has an interesting form of immortality--whenever he is killed a sleeping Gosseyn clone who has been receiving his memories is woken and is effectively the same person.
M.H. Zool