Some people believe that being kind is a weakness, and nothing could be further from the truth. Being kind can make the difference between success and failure. It can make your life and relationships deeper and more meaningful. Kindness is a very powerful tool that will deliver you from feeling lonely and open doors to a life that is filled with warmth.

Some people cover up their emotional pain with a surly attitude that pushes others away. But most of us want more, not less, human contact.

By simply being kind, you can open up all kinds of doors and maybe even a few hearts.

To display kindness, you have to know what it feels like. So a little homework is in order here. First, do a mental search of the times when people were kind to you, and write these times down. As you write, other memories and thoughts will come into your head. Record these as well. Then make a second list of times when you’ve been kind to other people. Once you complete your lists, look at the length of each. Are they equal, or does one vastly outweigh the other?

If it looks as if you have been the giver, but you don’t seem to be getting much in return, consider the people you have been giving your best self to. If you’ve been getting much more than you have been giving, it’s time to balance the books and start putting out more kindness.

Kind deeds are one way of showing kindness. So is volunteer work. Don’t expect any of the people you are helping to become your friends. This is a one-way street.

By extending yourself to others, you light up a silent path that says, “Hey, I’m a good person and willing to treat you well if you do the same to me.” It’s all mentally internal, but this kind of nonverbal message can speak very loudly to the right people.

— Dr. Barton Goldsmith, a psychotherapist in Westlake Village, California, is the author of “The Happy Couple: How to Make Happiness a Habit One Little Loving Thing at a Time.”