I can't go to the movies, or read a book, or open the New York Times without becoming depressed (the only cheering news was Labour's recent, much-awaited victory - I am amazed at how it quickened my blood, and I'm not even British). I find it depressing to get depressed. That's why I left Toronto for California. It's harder to be depressed when the sun shines every day and I can walk my three dogs by the ocean and in the mountains.

What is so wonderful about that, you may ask? You are not alone. I have my sceptical friends who wonder about my love for dogs. "You can't have an intelligent conversation with a dog," they point out (as if I were having one with them - memorable conversations, in any event, I can count on one hand). "They don't compose operas or go to concerts."

"They have no history of their species, no theories about ours," said another friend. "How intelligent is a dog anyway? They don't even rank up there with chimps," according to yet another.

My answer is that I have never figured out exactly why I should prize intelligence so highly. Nor is the history of our species something to be proud of. What good, exactly, is the ability to observe the unthinkable? Yes, we have chronicles of the Holocaust, but we also had the Holocaust itself. I notice that people are constantly trying to shore up the reputation of this rather disreputable species. Humans like to make comparisons in which we come out on top. My critics say I suffer from anthropomorphism, the disease of attributing to animals thoughts and feelings which they could not possibly have (notice how this begs the question). I reply that they are suffering from the disease of anthropocentrism, the belief that we are unique. I find it highly suspicious that we only seem to investigate those qualities we are sure we possess in greater abundance than other species. That is my explanation for why nobody has written a book about the emotions of dogs.

It is because dogs clearly emerge as superior to us when it comes to feeling purely, intensely and deeply.

Consider disappointment: can any creature look as distraught as a dog when you tell him that he is not coming on a walk with you? His ears fall and he throws himself onto the floor in complete despair, looking up at you with eyes filled with the hurt of pure betrayal. Or consider the opposite: you change your mind and tell your dog that, yes, he is coming with you. Up he bounds from the floor, he begins to wind himself into crazy circles, moaning with pleasure. He leaps in the air, he barks from sheer delight. He is the very picture of joy, of pure, unalloyed happiness.

Think of the money spent in Britain each year by humans visiting therapists to find out what they feel. We are certainly superior to dogs when it comes to hiding our feelings, not only from each other, but even from ourselves. It is, in a way, quite pitiful. In one of the few true things he said, Freud once wrote about a man who loved a woman for six years, but only found out about it years later. We cannot even imagine such a situation among our canine superiors. They don't just feel, they are their feelings.

When I go to the dogs to observe their emotions, I go for two reasons: to study them (how did they become this way?) and to learn from them how I can become more like a dog. Every moment seems infused by them with heightened feelings. They never need to compare one situation with another. Walking the streets of downtown Berkeley this morning, I was suddenly reminded of how beautiful London is in comparison. I looked with distaste at the dilapidated, featureless buildings lining University Avenue. Then I looked at my dogs: they were intensely eager to explore every corner of the avenue. They live in the present. I took them last week to a filthy little beach near the race-track in Berkeley. They raced out of the car, and threw themselves in the sand as if they had never seen sand before. They excitedly dug holes, then ran to the water and splashed in the waves and emerged with a look of "Isn't this wonderful? Aren't you glad we came?" I had to stop thinking about Cannes, and agree with them. Because if I didn't, then I was only human, and if I did, then I could begin to be more like them, more like a dog.

I am not a religious man, and I pause before using the word soul. But my experiences with the dogs in my life convince me that there is some profound essence, something about being a dog, that corresponds to our notion of an inner soul, the core of our being that makes us most human.

In human animals, this core, I am convinced, has to do with our ability to reach out and help a member of another species, to devote our energy to the welfare of that species, even when we do not stand to benefit from the other - in short, to love the other for its own sake. If any species on earth shares this miraculous ability with us (and perhaps there are many more we do not yet know about), it is the dog, for the dog truly loves us sometimes beyond expectation, beyond measure, beyond what we deserve - more, indeed than we love ourselves.