“Is power that—an emptiness?”

Sappho, act 1, sc. 5 (1818).

Source: Who Is Man? (1965), Ch. 5<!-- The sense of the ineffable, p. 87 -->
Context: In our reflection we must go back to where we stand in awe before sheer being, faced with the marvel of the moment. The world is not just here. It shocks us into amazement.
Of being itself all we can positively say is: being is ineffable. The heart of being confronts me as enigmatic, incompatible with my categories, sheer mystery. My power of probing is easily exhausted, my words fade, but what I sense is not emptiness but inexhaustible abundance, ineffable abundance. What I face I cannot utter or phrase in language. But the richness of my facing the abundance of being endows me with marvelous reward: a sense of the ineffable.

On the title of her book Love (2003), in O, The Oprah Magazine (November 2003) http://www.oprah.com/omagazine/200311/omag_200311_toni_b.jhtml
Context: It is easily the most empty cliché, the most useless word, and at the same time the most powerful human emotion — because hatred is involved in it, too. I thought if I removed the word from nearly every other place in the manuscript, it could become an earned word. If I could give the word, in my very modest way, its girth and its meaning and its terrible price and its clarity at the moment when that is all there is time for, then the title does work for me.

Statement of President Obama on the death of Vaclav Havel (18 December 2011) http://www.whitehouse.gov/the-press-office/2011/12/18/statement-president-obama-death-vaclav-havel
2011
Context: Having encountered many setbacks, Havel lived with a spirit of hope, which he defined as “the ability to work for something because it is good, not just because it stands a chance to succeed.” His peaceful resistance shook the foundations of an empire, exposed the emptiness of a repressive ideology, and proved that moral leadership is more powerful than any weapon. He played a seminal role in the Velvet Revolution that won his people their freedom and inspired generations to reach for self-determination and dignity in all parts of the world.

As quoted in Asadollah Alam (1991), The Shah and I: The Confidential Diary of Iran's Royal Court, 1968-77, page 465
Attributed

Source: Memory, Sorrow, and Thorn, To Green Angel Tower (1993), Part 2, Chapter 4, “A Thousand Leaves, A Thousand Shadows” (p. 99).

Said to Tommie Smith and John Carlos, who had given the black power salute while receiving their Olympic medals
Jesse Owens, Champion Athlete (1990)

Source: Ivanhoe (1819), Ch. 29, Ivanhoe explains to Rebecca the virtues of chivalry.