These insults are from an era before the English language got boiled down to 4-letter words.
1. "He had delusions of adequacy ” Walter Kerr
2. "He has all the virtues I dislike and none of the vices I admire.”- Winston Churchill
3. "I have never killed a man, but I have read many obituaries with great pleasure. - Clarence Darrow
4. "He has never been known to use a word that might send a reader to the dictionary.”-William Faulkner (about Ernest Hemingway)
5. "Poor Faulkner. Does he really think big emotions come from big words?"- Ernest Hemingway (about William Faulkner)
6. "Thank you for sending me a copy of your book; I'll waste no time reading it.” - Moses Hadas
7. "I didn't attend the funeral, but I sent a nice letter saying I approved of it.” - Mark Twain
8. "He has no enemies, but is intensely disliked by his friends.” - Oscar Wilde
9. "I am enclosing two tickets to the first night of my new play; bring a friend, if you have one.” -George Bernard Shaw to Winston Churchill
10. "Cannot possibly attend first night, will attend second... if there is one.” - Winston Churchill, in response
11. "I feel so miserable without you; it's almost like having you here” - Stephen Bishop
12. "He is a self-made man and worships his creator.” - John Bright
13. "I've just learned about his illness. Let's hope it's nothing trivial.” - Irvin S. Cobb
14. "He is not only dull himself; he is the cause of dullness in others.” - Samuel Johnson
15. "He is simply a shiver looking for a spine to run up. - Paul Keating
16. "He loves nature in spite of what it did to him.” - Forrest Tucker
17. "Why do you sit there looking like an envelope without any address on it?” - Mark Twain
18. "His mother should have thrown him away and kept the stork.” - Mae West
19. "Some cause happiness wherever they go; others, whenever they go.” - Oscar Wilde
20. "He uses statistics as a drunken man uses lamp-posts... for support rather than illumination.” - Andrew Lang (1844-1912)
21. "He has Van Gogh's ear for music.” - Billy Wilder
22. "I've had a perfectly wonderful evening. But I'm afraid this wasn't it.” - Groucho Marx
23. The exchange between Winston Churchill & Lady Astor: She said, "If you were my husband I'd give you poison." He said, "If you were my wife, I'd drink it."
24. "He can compress the most words into the smallest idea of any man I know." - Abraham Lincoln
25. "There's nothing wrong with you that reincarnation won't cure." -- Jack E. Leonard
26. "They never open their mouths without subtracting from the sum of human knowledge." -- Thomas Brackett Reed
27. "He inherited some good instincts from his Quaker forebears, but by diligent hard work, he overcame them." -- James Reston (about Richard Nixon) —Robert L Truesdell