“We are as great as our belief in human liberty — no greater. And our belief in human liberty is only ours when it is larger than ourselves.”

Original: (it) Qualsiasi emozione influisce sui nostri pensieri, le nostre credenze e le nostre azioni. Le forti emozioni positive esercitano un grande potere sul corpo umano e sul mondo intero.
Source: prevale.net

Postscript
1900s, The Varieties of Religious Experience (1902)
Context: The ideal power with which we feel ourselves in connection, the 'God' of ordinary men, is, both by ordinary men and by philosophers, endowed with certain of those metaphysical attributes which in the lecture on philosophy I treated with such disrespect. He is assumed as a matter of course to be 'one and only,' and to be 'infinite'; and the notion of many finite gods is one which hardly any one thinks it worth while to consider, and still less to uphold. Nevertheless, in the interests of intellectual clearness, I feel bound to say that religious experience, as we have studied it, cannot be cited as unequivocally supporting the infinitist belief. The only thing that it unequivocally testifies to is that we can experience union with something larger than ourselves and in that union find our greatest peace. Philosophy, with its passion for unity, and mysticism with its monoideistic bent, both 'pass to the limit' and identify the something with a unique God who is the all-inclusive soul of the world. Popular opinion, respectful to their authority, follows the example which they set.

Source: The Neverending Story

"To the Indianapolis Clergy." The Iconoclast (Indianapolis, IN) (1883)
Context: I account in part for the civilization of America by the fact that our fathers were wise enough, and jealous of each other enough, to absolutely divorce church and state. They regarded the church as a dangerous mistress—one not fit to govern a president. This divorce was obtained because men like Jefferson and Paine were at that time prominent in the councils of the people. There is this peculiarity in our country—the only men who can be trusted with human liberty are the ones who are not to be angels hereafter. Liberty is safe so long as the sinners have an opportunity to be heard.

Looking for an Honest Man (2009)
Context: Diogenes … refuses to be taken in by complacent popular belief that we already know human goodness from our daily experience, or by confident professorial claims that we can capture the mystery of our humanity in ­definitions. But mocking or not, and perhaps speaking better than he knew, Diogenes gave elegantly simple expression to the humanist quest for self-knowledge: I seek the human being — my human being, your human being, our humanity. In fact, the embellished version of Diogenes' question comes to the same thing: To seek an honest man is, at once, to seek a human being worthy of the name, an honest-to-goodness exemplar of the idea of humanity, a truthful and truth-speaking embodiment of the animal having the power of articulate speech.

Independence Day speech (1828)

It is that unique self-definition which has given us an exceptional appeal, but it also imposes on us a special obligation, to take on those moral duties which, when assumed, seem invariably to be in our own best interests.
Presidency (1977–1981), Inaugural Address (1977)

2013, Remarks on Economic Mobility (December 2013)

Presidency (1977–1981), The Crisis of Confidence (1979)
Context: I know, of course, being President, that government actions and legislation can be very important. That's why I've worked hard to put my campaign promises into law — and I have to admit, with just mixed success. But after listening to the American people I have been reminded again that all the legislation in the world can't fix what's wrong with America. So, I want to speak to you first tonight about a subject even more serious than energy or inflation. I want to talk to you right now about a fundamental threat to American democracy.
I do not mean our political and civil liberties. They will endure. And I do not refer to the outward strength of America, a nation that is at peace tonight everywhere in the world, with unmatched economic power and military might.
The threat is nearly invisible in ordinary ways. It is a crisis of confidence. It is a crisis that strikes at the very heart and soul and spirit of our national will. We can see this crisis in the growing doubt about the meaning of our own lives and in the loss of a unity of purpose for our Nation.
The erosion of our confidence in the future is threatening to destroy the social and the political fabric of America.
The confidence that we have always had as a people is not simply some romantic dream or a proverb in a dusty book that we read just on the Fourth of July.
It is the idea which founded our Nation and has guided our development as a people. Confidence in the future has supported everything else — public institutions and private enterprise, our own families, and the very Constitution of the United States. Confidence has defined our course and has served as a link between generations. We've always believed in something called progress. We've always had a faith that the days of our children would be better than our own.
Our people are losing that faith, not only in government itself but in the ability as citizens to serve as the ultimate rulers and shapers of our democracy. As a people we know our past and we are proud of it. Our progress has been part of the living history of America, even the world. We always believed that we were part of a great movement of humanity itself called democracy, involved in the search for freedom, and that belief has always strengthened us in our purpose. But just as we are losing our confidence in the future, we are also beginning to close the door on our past.