The Navy is a master plan designed by geniuses for execution by idiots.
Thomas Keefer makes this observation to Willie Keith while the two are sitting in the wardroom decoding messages. The quotation sums up Keefer's view of the Navy, and explains why he is so offended by the Navy. Keefer is a generous, smart person, employed in a task that a monkey could perform. When Keefer is later promoted to a position of command, however, he performs terribly, which suggests that even smart men are not automatically fit for command. This quotation shows Keefer's scorn for the Navy, a scorn that he instills in all those around him. Willie, who is still in a formative stage onboard the Caine, internalizes these words of Keefer's. Keefer presents a problem because he offhandedly poisons the very thing that keeps the Navy running during wartime: fresh meat.
Get this through your thick Reserve head, the heat is on. I'll be the guy everybody will hate. That's okay. I'm the exec of this ship, and I'll carry out my orders, do you hear?"
Lieutenant Gorton makes this heated reply to Thomas Keefer when the novelist protests at being punished for allowing Willie to leave the ship without consulting Gorton first. This event comes in the infant days of Queeg's captainship, and the order for Keefer's punishment is actually coming from the captain, not Gorton. This quotation highlights the conflict between the reserve sailors, such as Keefer, and the regular Navy men, such as Gorton. In this quotation, Keefer represents the model of a good executive officer, carrying out the will of his commanding officer without allowing his friendships to interfere.
You can't assume a goddamned thing in the Navy.
This line becomes Captain Queeg's catchphrase. It is first used when Queeg reprimands Burt Gorton for not giving him a more complete estimation of the difficulty involved in recovering a target after the towline-cutting incident. Queeg always uses this line when reassigning the blame for incidents in which he was at fault. Later, after two people present evidence that the steward's mates had eaten the strawberries, Queeg again falls back on this sentiment, urging the search for a key to go on. In that instance, the line is proof of Queeg's stubborn desire to reenact an earlier success in which a key was found.
[Willie's] mind was full of the flight that lay ahead. He was going to make May his wife. He did not know what manner of life they would find together, and he did not care now."
The narrator of The Caine Mutiny tells us this as Willie departs from interrupting May Wynn's rehearsal after decommissioning the Caine. This passage is proof that Willie has fully matured and is living the advice his father gave him in his last letter. In that letter, Mr. Keith cited Ecclesiastes, which says, "Whatsoever thy hand findeth to do, do it with thy might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, whither thou goest." Willie is living in the moment and putting all of his effort into making May his wife, regardless of money or future difficulties. He has realized that regret will be the only thing that matters when he dies, and is working to eliminate all traces of it.
You've grown up. You know everything I can tell you. If you're still seeking out May, she must have qualities I've never had a chance to observe I wouldn't want to be shut out of your life, whatever you do. I'm rather short on sons.
When Willie confronts his mother with his desire to make May Wynn his wife, she responds in this way. Coming into the discussion, Willie thought that he was making a choice between his wife and his mother. Instead, he learns that his mother has come to terms with the fact that he has become a man, and that she only wants what is best for her son. Willie's happiness and their continuity as a family has become Mrs. Keith's priority.