The Pawns Of Null A by A. E. van Vogt

A fast-paced sequel following Gilbert Gosseyn, an unusually gifted man trained in non‑Aristotelian logic, as he becomes embroiled in a vast conspiracy that manipulates identities and political power; confronting alien influences, engineered pawns, and shadowy forces seeking control of humanity, he must use his extraordinary mental skills to unravel the plot, survive repeated attempts on his life, and determine who truly holds the future.