Who is Tristram Foxe from The Wanting Seed and what is their importance?

Tristram Foxe undergoes the greatest personality changes of any character in the novel. At first, he is a rather bland and timid soul. He is a history teacher at a boys' school who lives a quiet life, obeys the rules, and does not even complain about his wife's lack of sexual interest in him. When their small child dies at the start of the book, he seems to accept the tragedy without much emotion. The only small rebellion in his life is to teach his indifferent students about a theory of cyclical phases in history that is not an approved part of the curriculum. Tristram has no idea that his wife is cheating on him with his own brother, but when he learns of it, the anger he feels is like an awakening after a long slumber. His imprisonment further fuels this anger, which becomes rage and bitterness that give him the courage to break out of prison. Full of thoughts of revenge, he braves the dangerous outside world, and the experiences he has in the countryside and later, in the military, are devastating. He goes through a long period of psychic and physical sickness caused by the corruption and violence he not only has witnessed but in which he has partaken. Yet he emerges from his convalescence stronger, more resourceful and, most important of all, without the thirst for vengeance that had been crippling his soul. By the time that he reunites with his wife at the novel's end, he is much wiser and more in control of his life than at the start of the story. The implication is that he accordingly will be a much better husband and father than he was than before all the trials that he endured.