There are all sorts of good sensible, civilised reasons to avoid getting angry.

Not only does it make you feel bad, it makes you do stupid things without noticing the risks and it can be self-destructive.

As a result civilised people do their best to suppress, redirect and mask their anger. Most of us treat our anger as though it's unreasonable, unshowable and unmentionable.

But like all emotions anger has its purposes, which can be used to good effect.

Anger is a motivating force

You sometimes hear people talking about using anger as a motivating force by 'turning anger into positive energy'. In fact anger itself is a kind of positive energy and a powerful motivating force. Research has shown that anger can make us push on towards our goals in the face of（面对） problems and barriers.

In one study participants were shown objects they associated with a reward. Some, though, were first exposed to angry faces. Those shown the angry faces were more likely to want objects they were subsequently exposed to (Aarts et al., 2010).

When we see something as beneficial, we want it more when we're angry. So, when used right, constructive anger can make you feel strong and powerful and help push you on to get what you want.

Angry people are more optimistic

It may sound like an odd thing to say, but angry people have something in common with happy people. That's because both tend to be more optimistic.

Take one study of fear of terrorism carried out in the aftermath of the 9/11 terrorist attacks. In this study those experiencing anger expected fewer attacks in the future (Lerner et al., 2003). In contrast those experiencing more fear were more pessimistic（悲观的，厌世的） about the future and expected further attacks.

Anger can benefit relationships

Anger is a natural reaction to being wronged by someone else and it's a way of communicating that sense of injustice. But society tells us anger is dangerous and we should hide it. What does this do to our personal relationships?

Oddly enough research has shown that hiding anger in intimate relationships can be detrimental (Baumeister et al., 1990). The problem is that when you hide your anger, your partner doesn't know they've done something wrong. And so they keep doing it. And that doesn't do your relationship any good.

The expression of anger, if justifiable and aimed at finding a solution rather than just venting, can actually benefit and strengthen relationships.

Anger provides self-insight

Anger can also provide insight into ourselves, if we allow it.

A sample of Americans and Russians were asked about how recent outbursts of anger had affected them (Kassinove et al., 1997). 55% claimed that getting angry had let to a positive outcome. One top of this one-third said that anger provided an insight into their own faults.

If we can notice when we get angry and why, then we can learn what to do to improve our lives. Anger can motivate self-change.

Anger reduces violence

Although anger often precedes physical violence, it can also be a way of reducing violence. That's because it's a very strong social signal that a situation needs to be resolved. When others see the signal they are more motivated to try and placate（抚慰） the angry party.

If you're still not convinced that anger might reduce violence, imagine a world without anger where people had no method for showing how they felt about injustice. Might they jump straight to violence?

Anger as negotiation strategy

Anger can be a legitimate way to get what you want. In one study of negotiation participants made larger concessions and fewer demands of an angry person than one who was happy (Van Kleef et al., 2002).

So there's some evidence that anger can be used as a negotiation strategy, but it's more complicated than that. You can't just lose your rag and expect to win everything you want.

Anger is likely to work best when it's justified, if you appear powerful and when the other side's options are limited (Sinaceur & Tiedens, 2006; Van Kleef et al., 2007).

In the right circumstances, then, it's possible to both get mad and get even.