When I got engaged, a friend passed along a piece of advice that she’d heard from her boss: “In a good marriage, both spouses leave three things unsaid each day.”

I was surprised. I thought her advice would be something like, “Remember to say ‘I love you,’” or “Be sure to say ‘Thanks.’” I couldn’t imagine why I would have to leave things unsaid.

Well, now I know. And I realize that this advice was tremendously useful.

I only manage to follow the advice part of the time, but just in the last few days, I’ve left unsaid the following statements:

 I’ve told you that three times already.
 You said you’d try to come, but are you really going to try?
 Can’t you do it this time?
 Don’t stay up late tonight and then, tomorrow afternoon, tell me that you need a nap.
 Can’t we talk about this now?

And these are just the statements I can think of off the top of my head.

Research backs up my friend’s advice to “leave things unsaid.” Studies show that one fact of human nature is that people have a “negativity bias”: we react to the bad more strongly and persistently than to the comparable good.

For example, within a marriage, it takes at least five good acts to repair the damage of one critical or destructive act.

So, by refraining from making an obnoxious comment, I’m actually doing a lot more to preserve the happiness of my marriage than by making a nice comment. The negative drags us down farther than the positive lifts us up.

Another fact of human nature is that, although we think that we act because of the way we feel, we actually feel because of the way we act. By changing our actions, we can change our emotions.

If I act critical, annoyed, or resentful, I’m going to feel critical, annoyed, or resentful. On the contrary, if I act considerate and patient, I’ll feel considerate and patient.

And the huge benefit is that not only do I feel nicer—by acting in a nicer way, I provoke a nicer response in my husband. Together, we change the atmosphere of our marriage.