Think about this for a minute. What it is to have a dog, another species, for a friend? A companion who will be there with you, day after day, asking little more than something to eat and a safe place to live.

I can take my dog's leash off and know that she'll return to me. She will chase critters, smell good smells, snack on fresh grass or play ball, but always with an eye on me. When she is done with her most current adventure, we'll go home together.

I can ask her to come to me and remain by my side, and she will choose to respond because it's our habit to cooperate with each other, even though she has freedom to choose otherwise. Yes, I trained these things but she does not follow my requests out of obedience. She follows because it works for both of us, to live in harmony together.

My friendship with this dog affects other people as well. Walkers, cyclists, and equestrians all smile as we pass by. My dog's joyful leaping and running infects other people with her happiness; a reminder of the pleasure of being curious and free. I am gratified to realize the power I have to make another living creature so joyful as she bounces and runs on our way out. Alone, it's just a walk, but with my dog it's our shared exploration.

And then I see people smile when we return. Now my dog walks quietly at my side, keeping me company. Everyone is happy to see our companionship. Things feel right in the world when a person is out with their dog, together with friendship.

There is no comparison between a person walking alone and a person walking with a dog. I have all of the benefits of solitude; time to think and breathe, but none of the disadvantages of being alone. I am not alone.

Not all dogs are so beautifully balanced, but a lot of dogs are, or have the potential to be. How amazing this is, a species that is not considered rare or valuable – just a dog that we take for granted, willingly staying in our homes and by our side. Dogs are widely available; many people can have one, which means that you can go out and adopt or buy a friend. Think about that. You can adopt or buy a friend. Doesn't even matter if you're a nice person – you can still have a friend.

I put in some time to get to friendship, but that wasn't work. As with all relationships, part of the pleasure was finding ways to have both of our needs met. I enjoyed her youthful silliness as well as the training time that gently helped mold her maturity. And now, as my dog approaches her twelfth birthday, I marvel at the connection we've built with little more than the natural capacity of our species to fall in love with each other.

I can pet her soft fur, share a snack, or we can walk. I can work on my computer and she'll be found asleep under my desk. And when I go to bed for the night, I know she'll sleep nearby. She is always there, waiting for me, for the price of her name.

In exchange for a few meals, the occasional walk, and a hand on her head when she asks for attention, I have a friend. Day after day, that's all it takes for my dog, a different species, to choose me. An animal living contentedly in my home and giving back to me in ways to numerous to count. A bit of a miracle, really.

If everyone had a dog for a friend – not because they thought they should get a dog, or to do dog sports, or to guard the house, or because families have dogs – if people got a dog for a friend, and then learned to treat that dog as a friend, the world would be a very different place. A kinder, warmer and better place.