“We are what our thoughts have made us; so take care about what you think. Words are secondary. Thoughts live; they travel far.”

"A Few Words to a Young Writer" http://www.ursulakleguin.com/WordsYoungWriter.html (2008)

Vol. 2, Ch. 22, § 257 "On Thinking for Yourself" as translated in Essays and Aphorisms(1970) as translated by R. J. Hollingdale
Variant translation: Just as the largest library, badly arranged, is not so useful as a very moderate one that is well arranged, so the greatest amount of knowledge, if not elaborated by our own thoughts, is worth much less than a far smaller volume that has been abundantly and repeatedly thought over.
Parerga and Paralipomena (1851), Counsels and Maxims

As rendered by T. Byrom (1993), Shambhala Publications.
There is no quote from the Pali Canon that matches up with any of these. The closest quote to this is in the Majjhima Nikaya 19:
"Whatever a monk keeps pursuing with his thinking & pondering, that becomes the inclination of his awareness. If a monk keeps pursuing thinking imbued with sensuality, abandoning thinking imbued with renunciation, his mind is bent by that thinking imbued with sensuality. If a monk keeps pursuing thinking imbued with ill will, abandoning thinking imbued with non-ill will, his mind is bent by that thinking imbued with ill will. If a monk keeps pursuing thinking imbued with harmfulness, abandoning thinking imbued with harmlessness, his mind is bent by that thinking imbued with harmfulness." Sources: http://www.accesstoinsight.org/tipitaka/mn/mn.019.than.html
Misattributed

Source: No Way Out (2002), Ch. 6: Seeking Strengthens Separation

Source: Prey

On his reationship with the press in Washington, D.C. and its role in a democracy
2017, Final News Conference as President (January 2017)
Context: We have traveled the world together. We did a few singles, a few doubles together. I’ve offered advice that I thought was pretty sound, like don’t do stupid stuff.(LAUGHTER) And even when you complained about my long answers, I just want you to know that the only reason they were long was because you asked six-part questions.(LAUGHTER)But I have enjoyed working with all of you. That does not, of course, mean that I’ve enjoyed every story that you have filed, but that’s the point of this relationship. You’re not supposed to be (inaudible) fans, you’re supposed to be skeptics, you’re supposed to ask me tough questions. You’re not supposed to be complimentary, but you’re supposed to cast a critical eye on folks who hold enormous power and make sure that we are accountable to the people who sent us here, and you have done that. And you have done it for the most part in ways that I could appreciate for fairness, even if I didn’t always agree with your conclusions. And having you in this building has made this place work better. It keeps us honest, it makes us work harder. You have made us think about how we are doing what we do and whether or not we’re able to deliver on what’s been requested by our constituents.

Source: How to Stop Worrying and Start Living

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