How we cite our quotes: (Line)
Quote #4
If you can bear to hear the truth you've spoken
Twisted by knaves to make a trap for fools, (13-14)
We again see a connection between stoicism and endurance. Here, that endurance takes the form of being able to watch "knaves" distort one's words in order to deceive people. Being able to "bear" something implies being able to observe without overreacting, getting too upset, and the like.
Quote #5
Or watch the things you gave your life to, broken,
And stoop and build 'em up with worn-out tools; (15-16)
The key word is "watch." Note that there is no mention of things like "get upset," "throw a fit," or "sulk." Nope. This is because to be truly stoic is to observe what has happened and to go about fixing it, without getting all bent out of shape.
Quote #6
If you can make one heap of all your winnings
And risk it on one turn of pitch-and-toss,
And lose, and start again at your beginnings,
And never breathe a word about your loss: (17-20)
These lines pick up right where lines 15-16 left off. This time it's not about "watching," but rather about "not breathing a word" about one's loss to anybody. These lines reiterate the point that, to be stoic, one must start over at times—without making a fuss.