In reading Steven Pinker’s How the Mind Works, which has been a slow burner (both in terms of time taken to read it and time taken to get into the really interesting stuff), I have just started to read about the importance and ontology of emotions. I came to a realisation, explicitly, that emotions are fundamental to our lives. Fundamental by way of giving us the reasons and desire to do all that we do. In fact, without emotion, we wouldn’t get anything done, and would undoubtedly not exist as a species, or as this species.

When we talk of purpose, we usually derive our life meaning, our purpose back to some sense of happiness, as many utilitarian philosophers have set out. But what is interesting is that without the emotional dimension to this, happiness would be pointless. This is rather tautologous because happiness is good since it makes you happy, as it were. The emotion of happiness, and the pain of sadness, and the emotional pain of (physical) pain itself mean that the key drivers for our sense of purpose are our emotions themselves. It is our ‘head’, our rational minds which go about codifying this and thinking of sensible ways in which to obtain this emotional happiness.

Perhaps Pinker describes this better (p. 375-6): 

The brain strives to put its owner in circumstances like those that caused its ancestors to reproduce. (The brain's goal is not reproduction itself; animals don't know the facts of life, and people who do know them are happy to subvert them, such as when they use contraception.) The goals installed [by natural selection] inHomo sapiens, that problem-solving, social species, are not just the four Fs [i.e., fight, flee, feed, mate]. High on the list are understanding the environment and securing the cooperation of others.

And here is the key to why we have emotions. An animal cannot pursue all its goals at once. If an animal is both hungry and thirsty, it should not stand halfway between a berry bush and a lake, as in the fable about the indecisive ass who starved between two haystacks. Nor should it nibble a berry, walk over and take a sip from the lake, walk back to nibble another berry, and so on. The animal must commit its body to one goal at a time, and the goals have to be matched with the best moments for achieving them.... Different goals are appropriate when a lion has you in its sights, when your child shows up in tears, or when a rival calls you an idiot in public.

The emotions are mechanisms that set the brain's highest-level goals. Once triggered by a propitious moment, an emotion triggers the cascade of subgoals and sub-subgoals that we call thinking and acting. Because the goals and means are woven into a multiple nested control structure of subgoals within subgoals within subgoals, no sharp line divides thinking from feeling, nor does thinking inevitably precede feeling or vice versa (notwithstanding the century of debate within psychology over which comes first). For example, fear is triggered by a signal of impending harm like a predator, a clifftop, or a spoken threat. It lights up the short-term goal of fleeing, subduing, or deflecting danger, and gives the goal high priority, which we experience as a sense of urgency. It also lights up the longer-term goals of avoiding the hazard in the future and remembering how we got out of it this time, triggered by the state we experience as relief. Most artificial intelligence researchers believe that freely behaving robots (as opposed to the ones bolted to the side of an assembly line) will have to be programmed with something like emotions merely for them to know at every moment what to do next. (Whether the robots would be sentient of these emotions is another question, as we saw in Chapter 2.)

Fear also presses a button that readies the body for action, the so-called fight-or-flight response. (The nickname is misleading because the response prepares us for any time-sensitive action, such as grabbing a baby who is crawling toward the top of a stairwell.) The heart thumps to send blood to the muscles. Blood is rerouted from the gut and skin, leaving butterflies and clamminess. Rapid breathing takes in oxygen. Adrenaline releases fuel from the liver and helps the blood to clot. And it gives our face that universal deer-in-the-headlights look.

Thus it is these physical and mental expressions of emotion (one could argue the mental expressions are merely conscious expressions of the more fundamental biological and physical processes) that drive us. We are simple animals, really…?