Steinbeck won the Nobel Prize for Literature in 1962. The presentation speech remarked specifically on five books from 1935 to 1939 and continued thus:

In this brief presentation it is not possible to dwell at any length on individual works which Steinbeck later produced. If at times the critics have seemed to note certain signs of flagging powers, of repetitions that might point to a decrease in vitality, Steinbeck belied their fears most emphatically with The Winter of Our Discontent (1961), a novel published last year. Here he attained the same standard which he set in The Grapes of Wrath. Again he holds his position as an independent expounder of the truth with an unbiased instinct for what is genuinely American, be it good or bad.

Ethan is not an entirely likeable character - but then that is what makes him realistic and easier to identify with. He has a secret 'place' down on the coast (a rcok seat in a cave) where he goes to be by himself. His meditations when there on one occasion expose him in one of his more likeable aspects. There is humour and pathos:

It sounds uncomfortable and silly, sitting cross-legged in a niche like a blinking Buddha, but some way the stone fits me, or I fit. Maybe I’ve been going there so long that my behind has conformed to the stones. As for its being silly, I don’t mind that. Sometimes it’s great fun to be silly, like children playing statues and dying of laughter. And sometimes being silly breaks the even pace and lets you get a new start. When I am troubled, I play a game of silly so that my dear will not catch trouble from me. She hasn’t found me out yet, or if she has, I’ll never know it. So many things I don’t know about my Mary, and among them, how much she knows about me. I don’t think she knows about the Place. How would she? I’ve never told anyone. It has no name in my mind except the Place—no ritual or formula or anything. It’s a spot in which to wonder about things. No man really knows about other human beings. The best he can do is to suppose that they are like himself.

A nod towards the classic philosophical 'Problem of Other Minds' there at the end of the paragraph. Solipsism is the technical term for the position which claims that our own self is the only reality we can rely on. It all might be a dream (Descartes) or we might be a brain in a vat. (The latter option was partially explored by Roald Dahl in his story Willaim and Mary [1959] - see here.) Find out more here (2 minutes with flaky graphics) or here (an 8 minute explanation).