This is Hidden Brain. I'm Shankar Vedantam.

When it comes to the thorniest issues in our lives, all of us face a dilemma.

If we can't get what we want, should we settle for what we can get?

We've all heard aphorisms like don't make the perfect the enemy of the good. They are designed to help us see that

logically speaking incremental progress toward a goal is better than no progress.

But what happens if you think something is morally wrong,

but agree to change it only a little?

Let's say, for example, you think killing animals little.

Let's say for example you think killing animals is wrong and it's ethical to be a vegetarian.

But you've always loved meat and non-vegetarian food is an important part of your diet, culture, and heritage.

If you cut back on your meat eating to just a couple days a week, you might reduce your

consumption of meat, but are you really taking an ethical stance against the killing of animals?

Meat eaters may mock you for waffling on your convictions.

Vegetarians won't see you as one of them.

Or let's say you were living in an apartheid state,

like South Africa in the 1970s and 1980s.

You're a policymaker, and you recognize

a system of racial segregation is unjust.

You decide to make life better for some victims.

Perhaps you provide better sanitation,

or install street lights in a poor neighborhood.

Are you being virtuous or complicit?

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