Because most of us routinely read emotions in our dogs (wagging tail means happy, cringing means afraid, and so forth) it may be difficult to believe that the existence of real emotions in dogs was, and in some places still is, a point of scientific controversy. In the distant past, it was presumed that dogs had rich mental lives with feelings much like those of humans. However, with the rise of science things began to change. We learned enough about the principles of physics and mechanics, so that we could build complex machines, and began to notice that living things (both people and animals) were also based upon by systems governed by mechanical rules and chemical processes.

In the face of such discoveries, religions stepped in to suggest that there must be more to human beings than simply mechanical and chemical events. Church scholars insisted that people have souls, and the evidence they gave was that humans have consciousness and feelings. Animals might have the same mechanical systems, but they did not have a divine spark, and therefore they do not have the ability to experience true feelings.

Because most research at the time was church-sponsored it is not surprising that prominent scholars, such as the French philosopher and scientist René Descartes adopted this viewpoint. In a highly influential set of analyses, Descartes suggested that animals like dogs were simply some kind of machine. He would thus describe my Beagle, Darby, as simply being a dog-shaped chassis, filled with the biological equivalent of gears and pulleys. Although this machine doesn't have consciousness and emotions it can still be programmed to do certain things.

In recent times, science has progressed a long way beyond Descartes and we now understand that dogs have all of the same brain structures that produce emotions in humans. Dogs also have the same and undergo the same chemical changes that humans do during emotional states. Dogs even have the hormone , which, in humans, is involved with feeling love and affection for others. With the same neurology and chemistry that people have, it seems reasonable to suggest that dogs also have emotions that are similar to ours. However, it is important to not go overboard and immediately assume that the emotional ranges of dogs and humans are the same.

To understand what dogs feel, we must turn to research that was done to explore the emotions of humans. Not all people have the full range of all possible emotions. In fact, at some points in your life, you did not have the full complement of emotions that you feel and express today. Research shows that infants and young children have a more limited range of emotions, but over time the child's emotions begin to differentiate and they come to be able to experience different and more complex emotional states.

This data is important to our understanding of the emotional lives of dogs because researchers have come to believe that the mind of a dog is roughly equivalent to that of a human who is 2- to 2-and-a-half-years of age. This conclusion holds for most mental abilities, including emotions. Thus we can look to the human research to see what we might expect of our dogs. Like a young child, dogs will clearly have emotions, but many fewer kinds of emotions than we find in adults.

I’ve illustrated this in the accompanying illustration. At birth, a human infant only has an emotion that we might call excitement. This indicates how aroused he is, ranging from calm up to a state of frenzy. Within the first weeks of life, the excitement state comes to take on a positive or a negative flavor, and we can now detect the general emotions of contentment and distress. In the next couple of months, disgust, , and , become detectable in the infant. Joy often does not appear until the infant is nearly six months of age and it is followed by the emergence of or suspicion. True affection (the sort that it makes sense to use the label “love”) does not fully emerge until nine or ten months of age.

The complex social emotions, those which have elements that must be learned, don’t appear until late. and pride take more than three years to appear, while appears around six months after these. A child must be nearly four years of age before it feels contempt.

Source: Stan Coren

This developmental sequence is the golden key to understanding the emotions of dogs. Dogs go through their developmental stages much more quickly than humans do, and have all of the emotional range that they will ever achieve by the time they are four to six months of age (depending on the rate of maturing in their breed). However, we know that the assortment of emotions available to the dog will not exceed that which is available to a human who is 2- to 2-and-a-half-years old. This means that a dog will have all of the basic emotions: joy, fear, anger, disgust, and even love. However, based on current research it seems likely that your dog will not have those more complex emotions like guilt, pride, and shame.

Many people might argue that they have seen evidence that indicates their dog is capable of experiencing guilt. The usual situation is when you come home and your dog starts slinking around and showing discomfort, and you then find that he or she has left a smelly brown deposit on your kitchen floor. It is natural to conclude that the dog was acting in a way that shows that it is feeling guilty about the transgression. However this is not guilt, but simply the more basic emotion of fear. The dog has learned that when you appear and his droppings are visible on the floor, bad things happen to him. What you see is his fear of , he will never feel guilt.

So what does this mean for those of us who live with, and interact with dogs? The good news is that you can feel free to dress your dog in that silly costume for a party. He will not feel shame, regardless of how ridiculous he looks. He will also not feel pride at winning a prize at a dog show or an obedience . However your dog can still feel love for you, and contentment when you are around. Aren't these the emotions we truly value?

Stanley Coren is the author of many books including Born to Bark; Do Dogs Dream? The Modern Dog

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