“Whorf's brilliant analysis… seemed to support the view that man is a prisoner of his language.”

Word Play (1974)
Context: The weakness of the Sapir-Whorf Hypothesis... the impossibility of generalizing about entire cultures and then attributing these generalizations to the language spoken... is to leave numerous facts about culture unexplained. The great religions of the world... have flourished among diverse peoples who speak languages with sharply different grammars.... Cultures as diverse as the Aztec Empire of Mexico and the Ute hunting bands of the Great Basin spoke very closely related tongues.

Prof. George Cardona in:"Indo-Aryan languages".

As quoted in A Thousand Days: John F. Kennedy in the White House (1965) by Arthur M. Schlesinger, Jr., p. 291 books.google https://books.google.de/books?id=uFhNxX5lrNEC&pg=PA291&dq=stupidity

Golden Sayings of Epictetus
Context: You are impatient and hard to please. If alone, you call it solitude: if in the company of men, you dub them conspirators and thieves, and find fault with your very parents, children, brothers and neighbours. Whereas when by yourself you should have called it Tranquillity and Freedom: and herein deemed yourself like unto the Gods. And when in the company of the many, you should not have called it a wearisome crowd and tumult, but an assembly and a tribunal; and thus accepted all with contentment. What then is the chastisement of those who accept it not? To be as they are. Is any discontented with being alone? let him be in solitude. Is any discontented with his parents? let him be a bad son, and lament. Is any discontented with his children? let him be a bad father.—"Throw him into prison!"—What prison?—Where he is already: for he is there against his will; and wherever a man is against his will, that to him is a prison. Thus Socrates was not in prison since he was there with his own consent. (31 & 32).

Though this has been quoted extensively as if it were a statement of Wittgenstein, it was apparently first published in A Brief History of Time (1988) by Stephen Hawking, p. 175, where it is presented in quotation marks and thus easily interpreted to be a quotation, but could conceivably be Hawking paraphrasing or giving his own particular summation of Wittgenstein's ideas, as there seem to be no published sources of such a statement prior to this one. The full remark by Hawking reads:
: Philosophers reduced the scope of their inquiries so much that Wittgenstein, the most famous philosopher of this century, said, “The sole remaining task for philosophy is the analysis of language.” What a comedown from the great tradition of philosophy from Aristotle to Kant!
Disputed

The Day of the Triffids (1951), ch 9 - p.162

Letter to Gilbert Murray (25 October 1948), quoted in Gilbert Murray : An Unfinished Autobiography (1960) edited by Jean Smith and Arnold Toynbee, p. 179

Introduction
Bards of the Bible, 1850