“Democracy means the belief that humanistic culture should prevail.”

Existence (1956) p. 39; also published in The Discovery of Being : Writings in Existential Psychology (1983), Part III : Contributions to Therapy, Ch. 6 : To Be and Not to Be, p. 94
Existence (1958)
Context: It is interesting that the term mystic is used in this derogatory sense to mean anything we cannot segmentize and count. The odd belief prevails in our culture that a thing or experience is not real if we cannot make it mathematical, and that somehow it must be real if we can reduce it to numbers. But this means making an abstraction out of it … Modern Western man thus finds himself in the strange situation, after reducing something to an abstraction, of having then to persuade himself it is real. … the only experience we let ourselves believe in as real, is that which precisely is not.

“Planet Facebook Owns It,” http://www.ilanamercer.com/phprunner/public_article_list_view.php?editid1=652 WorldNetDaily.com, May 25, 2012.
2010s, 2012

"Journeying to democracy" in The Boston Globe (18 October 2007) http://www.boston.com/bostonglobe/editorial_opinion/oped/articles/2007/10/18/journeying_to_democracy/
Context: I fully understand the men behind Al Qaeda. They have tried to assassinate me twice before. The Pakistan Peoples Party and I represent everything they fear the most — moderation, democracy, equality for women, information, and technology. We represent the future of a modern Pakistan, a future that has no place in it for ignorance, intolerance, and terrorism.
The forces of moderation and democracy must, and will, prevail against extremism and dictatorship. I will not be intimidated. I will step out on the tarmac in Karachi not to complete a journey, but to begin one. Despite threats of death, I will not acquiesce to tyranny, but rather lead the fight against it.

Sabhal Mòr Ostaig Lecture (December 19, 2007)

Hanukkah dinner speech http://www.villagevoice.com/news/0550,lombardi,70903,2.html at Yeshiva University (December 2005)
Senate years (2001 – January 19, 2007)

Journal entry (20 June 1899); as published in Souvenirs and Prophecies: the Young Wallace Stevens (1977) edited by Holly Stevens, Ch. 3

In A Man Without a Country (2005) p. 80–81 Vonnegut makes a very similar statement:
God Bless You, Dr. Kevorkian (1999)
Context: About belief or lack of belief in an afterlife: Some of you may know that I am neither Christian nor Jewish nor Buddhist, nor a conventionally religious person of any sort.
I am a humanist, which means, in part, that I have tried to behave decently without any expectation of rewards or punishments after I'm dead. My German-American ancestors, the earliest of whom settled in our Middle West about the time of our Civil War, called themselves "Freethinkers," which is the same sort of thing. My great grandfather Clemens Vonnegut wrote, for example, "If what Jesus said was good, what can it matter whether he was God or not?"
I myself have written, "If it weren't for the message of mercy and pity in Jesus' Sermon on the Mount, I wouldn't want to be a human being. I would just as soon be a rattlesnake."

"One woman’s struggles" https://www.sundaystandard.info/ococaone-womanocos-strugglesoco/ (24 March 2014)

“It is time to recognize the contribution of whistleblowers” – UN expert welcomes commutation of Manning’s sentence
2017, Whistleblowers