It's the action, not the fruit of the action, that's important. You have to do the right thing. It may not be in your power, may not be in your time, that there'll be any fruit. But that doesn't mean you stop doing the right thing. You may never know what results come from your action. But if you do nothing, there will be no result.
Few will have the greatness to bend history itself, but each of us can work to change a small portion of events. It is from numberless diverse acts of courage and belief that human history is shaped. Each time a man stands up for an ideal, or acts to improve the lot of others, or strikes out against injustice, he sends forth a tiny ripple of hope, and crossing each other from a million different centers of energy and daring those ripples build a current which can sweep down the mightiest walls of oppression and resistance.
To me it seems that too many young women of this time share the same creed. 'Live, laugh, love, be nothing but happy, experience everything, et cetera et cetera.' How monotonous, how useless this becomes. What about the honors of Joan of Arc, Beauvoir, Stowe, Xena, Princess Leia, or women that would truly fight for something other than just their own emotions?
But more than that, if you ally yourself with people who are prepared to fight to make a difference, then your life will always be in danger. I don't think it's fair to ever blame the person who makes the stand. Because the Doctor's so old, because he's done this so many times before, he sometimes forgets how dangerous it is. But if he didn't create the danger by opposing evil, if he didn't get these people to help him, then terrible things would happen. Standing up for what's right is always the best thing to do.