Pessimism, I’ve found from personal experience, is a self-defeating prophecy.

Pessimists just can’t let themselves or anyone else win.They are the ones who look for five leaves in a field of four-leaf clovers.

I remember someone's comment that, as a pessimist, they’re always either right or pleasantly surprised, so it’s a win-win. Which is ironically optimistic, but also complete B.S. I realized, as I wondered why the statement annoyed me so; it was because I am an optimist and I’m still pleasantly surprised all the time.

My outlook, back when I was a cynical jerk who picked apart everything and pessimistically analyzed the world, led to the dismantling of every blessing, every situation, every person, into their underlying imperfections and mistakes and failures.

So I was always let down.

No good could be totally good, because I would find every implication of not good and hone it to a brilliant sheen, so it blotted out what enjoyment could be found. Pessimism is a slayer of joy. And the pessimist is not only a prisoner to their own whininess but is a dungeon master to the happiness of everyone around them. Cynicism is like a vortex of negative color.

Yes, optimists can be hurt very deeply, can be let down when good simply cannot be seen, but for the most part, when you live in a world you consider deeply, wonderfully beautiful and something to be called “good,” then injustice pulls the fighter from within you.

So you cling that much more furiously to goodness and light
Creating and guarding a beauty to hallow the night.

You don’t let the evil of the world drag you down with its inevitability.

Instead, you defy it and declare that IT IS NOT INEVITABLE.

Optimism has an inherent pledge to remind evil that it does not belong, and to fight it.

Optimists have reason to believe that they can win fights whereas pessimists aren’t given that hopeful motivation. So cynicism leads quite quickly to detached resignation in the face of evil; while idealism, however, naive it can be (though it does not have to be naive, and in fact is often less naive than cynicism), prompts outrage to action.

To quote Stephen Colbert:

Cynicism masquerades as wisdom, but it is the farthest thing from it. Because cynics don’t learn anything. Because cynicism is a self-imposed blindness, a rejection of the world because we are afraid it will hurt us or disappoint us. Cynics always say no. But saying “yes” begins things. Saying “yes” is how things grow."

So if you don't want to be a lazy, selfish coward, and you want to make the world a better place, look for the silver lining.

There is no sloth in the silver lining.