Professor Weston (full name Edward Rolles Weston) is arguably one of C. S. Lewis's greatest satanic characters. An eminent physicist on earth, he first appears in Lewis’s Out of the Silent Planet, which is the first in Lewis’s Space Trilogy. He is defeated by the novel's protagonist Elwin Ransom and the Oyarsa, the ruling angel or eldil of Mars (known to its inhabitants as "Malacandra"), but he returns in the second book of the trilogy in an attempt to wreak havoc on Perelandra (Venus), the "new Eden."
In Out of the Silent Planet, Weston first appears with his accomplice, Dick Devine (who later becomes Lord Feverstone in That Hideous Strength), attempting to abduct a mentally impaired youngster named Harry. They plan to take him to Malacandra (Mars) as a human sacrifice. It is then that they are surprised by Elwin Ransom, the main character of the novel, who is known to Devine. Devine persuades Weston to abduct Ransom instead.
In the course of their flight to Malacandra Ransom overhears a conversation between Weston and Devine that discloses to him their sinister purpose in abducting him. Shortly after their landing on Malacandra Weston and Devine attempt to drag Ransom to a towering, distant figure making its way across a lake to meet them. However, an accident occurs, in the form of a dangerous fish-type or crocodilian animal in the water (possibly a hnakra) distracting Ransom’s captors, and allowing him to flee. In the course of his adventures on Malacandra, Ransom learns that the Oyarsa, the being to whom he was to be ‘sacrificed’, wanted only to speak with one of his kind. That is, a human. However, the paranoid Weston cannot recognize true benevolence, and human sacrifice is the sort of superstition he expects from "primitive" cultures. It is eventually revealed that the (immediate) purpose of Weston’s and Devine’s journey to Malacandra is to mine gold, which the planet has in abundance (this is the primary motive of Devine, who is obsessed with money). Weston’s plan is to usher in a new age of space colonization to ensure the eternal survival of the human race, an idea borrowed from Stapledon's Last and First Men. The seeming humanitarianism of Weston's scheme is corrupted by his contemptuous and Machiavellian attitude towards all other forms of life (including intelligent ones).
The sudden arrival of Weston's self-designed spaceship on Perelandra (Venus) is a great surprise to the self-doubting Ransom, who himself has been sent by an oyarsa. Weston has undergone a philosophical conversion since his last appearance: he consider's his former devotion to the human race as `a mere prejudice', and now wishes to spread ‘Spirit’, or `the blind, inarticulate purposiveness' of emergent evolution. In his personal theology, Weston has come to the fatal misunderstanding that God and the Devil are one, and he works at the prompting of this syncretic Spirit: "In so far as I am the conductor of the central forward pressure of the universe, I am it ... I, Weston, am your God and Devil. I call that Force into me completely ...." From this moment of opening his soul, Weston is possessed by the Devil and lost as an independent personality.
The evil spirit possessing Weston works to corrupt the newly created race, tempting the Lady of Perelandra (the new Eve) into disobeying the commands of Maleldil (God), while Ransom pleads with her to resist the Un-man (Ransom’s name for Weston’s possessed body). Eventually Ransom, realizing that he cannot defeat the Un-man with argument — and prompted by Maleldil — physically attacks the Un-man and both are badly wounded during the ensuing fight.
Weston's consciousness appears to occasionally resurface, dismaying Ransom with the confusion and horror of Hell: `You try to connect things and can't. They take your head off ... and you can't even look back on what life was like ... because you know it never did mean anything even from the beginning.' However, it is impossible to distinguish whether anything he says is Weston or the Devil working through him. Indeed, Ransom concludes:
Ransom finally kills Weston’s body in the tunnels beneath Perelandra, and he rolls it into a volcanic abyss.
Ransom, having carved a monument to the great physicist into the wall outside the caverns, makes his way up the Fixed Land, to meet the grateful Lady and the King of the new planet.
According to Ransom's epitaph, Weston lived from 1896 to 1942 (Perelandra, chapter 15). However, the notion that he died at the age of 46 conflicts with Weston's explanation in Chapter 7 that he had neglected the study of biology "until I reached the fifties".
Weston may be a caricature of Cecil John Rhodes (1853-1902) an English South African businessman and imperialist politician. Like Rhodes, Weston is racist, amoral, rapacious, and hates God and religion. In a passing comment in That Hideous Strength, it is said that Great Britain has produced both heroes and villains, that for every King Arthur, there is a traitor Mordred, for every Sydney (the medieval poet), there is a Cecil Rhodes. In "Perelandra", Weston mentions his liking of the book of which Rhodes said "it made me who I am”: Winwood Reade’s The Martyrdom of Man, which expounded the ideology of secular humanism.
There is a glancing allusion to George Bernard Shaw: Weston's speech on Malacandra, like Back to Methuselah, ends with the words "It is enough for me that there is a Beyond", and Weston shares Shaw's (and Henri Bergson's) belief in the Life Force. Another possible influence is the philosopher Friedrich Nietzsche, the goal of whose philosophy was the advent of the "super-man". Weston is also similar to the villain Saruman from J.R.R. Tolkien’s The Lord of the Rings.
The choice of the name "Weston" might be more than accidental, considering that in his speech in Out of the Silent Planet he presents himself very much as the proponent of "Western Civilization" in its most expansionist and aggressive mode. (The names of the main villains in That Hideous Strength, "Wither" and "Frost", are clearly meant to reflect their characters.)
Professor Weston can also stand for the scientific elitism that despises all other types of knowledge.