“You're a historian. Tell me if there are any bath-tubs in history. I think they've been frightfully neglected.”

Source: A History of the World in 10½ Chapters

Source: Hogfather

1850 - 1870
Context: My dear Frédéric Bazille, I ask myself what you can be doing in Paris during fine weather, for I suppose that it must also be very fine there. Here my dear fellow, it is is charming, and I discover every day always beautiful things. It is enough to become mad [fou], so much do I have the desire to do it all, my head is cracking. Damn it, here it is the sixteenth, put aside your cliques and your claques, and come spend a couple of weeks here, it would be the best thing that you could do, because in Paris it cannot be very easy to work.
This very day, I still have a month to stay in; furthermore my sketches are becoming finished, I have even set to work additionally [remis] on some others. In sum, I am content enough with my stay here, even though my studies are very far from what I would wish. It is decidedly frightfully difficult to make something complete in all respects, and I think that there are scarcely any but those who content themselves with the approximate. Very well, my dear fellow, I want to struggle, scrape, start over again [recommencer], because one can do what one sees and understands, and it seems to me, when I see nature, that I am going to do it all, write it all out, but them go try to do it.... when one is on the job..
All this proves that one must only think about this. It is by force of observation and reflection that one finds. So let us grind away and grind away constantly. Are you making any progress? Yes, I am sure of it, but what I am sure of is that you do not work enough and not in the right way. It is not with carefree guys like your Villa and others that you will be able to work. It would be better all alone, and yet, all alone there are plenty of things that one cannot make out. In the end all of this is terrible, and it is a rough task.
... It is frightening what I see in my head.

Source: The Historian (2005), Ch. 5
Context: In the Year of Our Lord 1456 Drakula did many terrible and curious things. When he was appointed Lord in Wallachia, he had all the young boys burned who came to his land to learn the language, four hundred of them. He had a large family impaled and many of his people buried naked up to the navel and shot at. Some he had roasted and then flayed.
There was a footnote, too, at the bottom of the first page. The typeface of the note was so fine that I almost missed it. Looking more closely, I realized it was a commentary on the word impaled. Vlad Tepes, it claimed, had learned this form of torture from the Ottomans. Impalement of the sort he practiced involved the penetration of the body with a sharpened wooden stake, usually through the anus or genitals upward, so that the stake sometimes emerged through the mouth and sometimes through the head.
I tried for a minute not to see these words; then I tried for several minutes to forget them, with the book shut.
The thing that most haunted me that day, however, as I closed my notebook and put my coat on to go home, was not my ghostly image of Dracula, or the description of impalement, but the fact that these things had — apparently — actually occurred. If I listened too closely, I thought, I would hear the screams of the boys, of the “large family” dying together. For all his attention to my historical education, my father had neglected to tell me this: history’s terrible moments were real. I understand now, decades later, that he could never have told me. Only history itself can convince you of such a truth. And once you’ve seen that truth — really seen it — you can’t look away.

Source: This Side of Paradise

Republican National Convention http://65.126.3.86/reagan/html/reagan08_17_92.shtml (17 August 1992); (statement modeled after Lloyd Bentsen's jibe at Dan Quayle during debate in 1988)
Post-presidency (1989–2004)

Quoted in "Jacques Barzun '27: Columbia Avatar" http://www.college.columbia.edu/cct/jan06/cover.php by Thomas Vinciguerra, Columbia Today (January 2006)

"Are You Happy Now?"
2000s, Hotel Paper (2003)
Context: Now, don't just walk away. Pretending everything's okay, and you don't care about me. And I know there's just no use, when all your lies become your truths and I don't care. Could you look me in the eye? And tell me that you're happy now? Would you tell it to my face? Or have I been erased? Are you happy now? Are you happy now?