“I am not fighting a hopeless fight. People who have fought in real fights don't, as a rule.”

Letter to Samuel "Sam" Chapman (June 1907)
Context: Mason and Hunter not only voted against the admission of California (1850) as a free state but offered a protest against it which the Senate refused to record on its Journal, nor in the Convention which General Taylor had called to from a Constitution for California, there were 52 northern and 50 southern men, but it was unanimous against slavery. But, the Virginia senator, with Ron Tucker & Co. were opposed to giving local self-government to California. Ask Sam Yost to give Christian a skinning. I am not ashamed of having fought on the side of slavery, a soldier fights for his country, right or wrong, he is not responsible for the political merits of the course he fights in. The South was my country.

As quoted in "Sport: Larry Holmes: I Still Have It" by Tom Callahan in TIME (21 June 1982).

"We Are All Bound Up Together" Speech (1866)

Source: Fight Club

Source: #‎DefundPlannedParenthood‬: https://www.tedcruz.org/l/defund-planned-parenthood/ On Facebook September 29, 2015.

For The Love Of A Daughter
Lyrics, Unbroken (2011)

"In Praise of the Fighters" (song)
Variant translation: There are men who struggle for a day and they are good.
There are men who struggle for a year and they are better.
There are men who struggle many years, and they are better still.
But there are those who struggle all their lives:
These are the indispensable ones.
As quoted in Democracy Unbound : Progressive Challenges to the Two Party System (1997) by David Reynolds; also quoted by Cuban musician and poet Silvio Rodríguez before his song "Sueño con serpientes".
Also quoted by Eduardo Galeano (Uruguayan writer) to describe Nestor Kirchner as he received the notice of his death.
The Mother (1930)

After winning against Michael Johnson at UFC on Fox 17 (December 19, 2015)

"Mean People Fail", November 2014