“Courage is an animating spirit of masculinity, and it is crucial to any meaningful definition of masculinity. Courage and strength are synergetic virtues. An overabundance of one is worth less without and adequate amount of the other.”

Pg 25
The Way of Men (2012)
Context: Without strength, masculinity becomes something else- a different concept. Strength is not an arbitrary value assigned by human cultures. Increased strength is one of the fundamental biological differences between males and females. Aside from basic reproductive plumbing, greater strength is one of the most prominent, historically consequential and consistently measurable physical differences between males and females.

"Water", p. 113; this is often quoted as simply: Without courage, all other virtues are useless. <!-- Confessions of a Barbarian: Selections from the Journals of Edward Abbey, 1951-1989 (1994) p. 207 -->
Source: Desert Solitaire (1968)
Context: Has joy any survival value in the operations of evolution? I suspect that it does; I suspect that the morose and fearful are doomed to quick extinction. Where there is no joy there can be no courage; and without courage all other virtues are useless.

As quoted in USA Today (5 March 1988)
Variant:
Courage is the most important of all the virtues, because without courage you can't practice any other virtue consistently. You can practice any virtue erratically, but nothing consistently without courage.
As quoted in Diversity : Leaders Not Labels (2006) by Stedman Graham, p. 224

Source: 1930s, Education and the Social Order (1932), p. 107
Context: Belief in God and a future life makes it possible to go through life with less of stoic courage than is needed by skeptics. A great many young people lose faith in these dogmas at an age at which despair is easy, and thus have to face a much more intense unhappiness than that which falls to the lot of those who have never had a religious upbringing. Christianity offers reasons for not fearing death or the universe, and in so doing it fails to teach adequately the virtue of courage. The craving for religious faith being largely an outcome of fear, the advocates of faith tend to think that certain kinds of fear are not to be deprecated. In this, to my mind, they are gravely mistaken. To allow oneself to entertain pleasant beliefs as a means of avoiding fear is not to live in the best way. In so far as religion makes its appeal to fear, it is lowering to human dignity.

Pg 19-20
Becoming A Barbarian (2016)