This week all of America has sat aghast as more and more rain falls on Houston and more and more heartbreaking (and heroic) images emerge from the area. The terrible pictures have spurred those who know anyone in the area to reach out and offer support. (If you're not personally connected with the area, here's how to help.)

But what do you say when you manage to connect with someone who has been affected by a horrific event like Hurricane Harvey, or even a personal loss?

Even with the best of intentions, many of us can find ourselves tongue tied when confronted with other people's crises, unsure how to best offer comfort and avoid giving unintentional offense or causing greater emotional pain. Lifehacker has dug up a simple rule of thumb to help.

The handy principle comes from a 2013 Los Angeles Times editorial by psychologists Susan Silk and Barry Goldman. The piece was written in response to the many tone deaf comments Silk put up with while she was battling breast cancer, but the advice it contains is just as relevant to speaking with victims of natural disasters or any other type of crisis.

"Comfort in, dump out."

The rule developed by Silk and Goldman is just four words -- "comfort in, dump out" -- but to put it into practice you'll need to understand what the pair dub "the Ring Theory."

Draw a circle. This is the center ring. In it, put the name of the person at the center of the current trauma... Now draw a larger circle around the first one. In that ring put the name of the person next closest to the trauma.... Repeat the process as many times as you need to. In each larger ring put the next closest people. Parents and children before more distant relatives. Intimate friends in smaller rings, less intimate friends in larger ones. When you are done you have a Kvetching Order.

The basic idea is that comfort should flow from the outer rings towards the center. Bitching, moaning, and lamenting fate should only happen in the opposite direction.

"The person in the center ring can say anything she wants to anyone, anywhere. She can kvetch and complain and whine and moan and curse the heavens and say, 'Life is unfair' and 'Why me?' That's the one payoff for being in the center ring," Silk and Goldman explain. Those in the outer rings, however, can't kvetch inward.

So what can you say to those more affected by a crisis if you can't express your horror and sadness at what's happening to them? The short answer is whatever will help them most.

"Listening is often more helpful than talking. But if you're going to open your mouth, ask yourself if what you are about to say is likely to provide comfort and support. If it isn't, don't say it," instruct the psychologists. They go on to advise those offering comfort to avoid giving advice, talking about their own feelings, or comparing the other person's experiences to their own. Instead, try something as simple as "I'm sorry," or "This must really be hard for you," or "Can I bring you a lasagna/put your up for a few days/donate to your GoFundMe page?"

Which doesn't mean you can't vent your sadness and anger. You just can't vent it towards the center of the circle. "If you want to scream or cry or complain, if you want to tell someone how shocked you are or how icky you feel, or whine about how it reminds you of all the terrible things that have happened to you lately, that's fine. It's a perfectly normal response. Just do it to someone in a bigger ring," the pair concludes.