There is nothing more human than emotions. Homo sapiens have such a wide emotional spectrum that it’s difficult to imagine the species without it. In fact, we probably wouldn’t be a species without it. Emotions have not only ensured our long-term survival, but they have made us Earth’s apex organism. Unsurprisingly, the ways in which they have accomplished this feat go far beyond making us smile when good things happen and frown when bad things happen. As you will learn from this article, emotions are algorithms that do cost/benefit calculations which inform our actions. I’m serious. Keep reading to find out more.

They Are the Software in Our Hardware

Since we’re living in the digital age, algorithm is the perfect analogy for emotion. Historian Yuval Noah Harari knew this when he focused much of his book Homo Deus on the emotional process in humans and its similarity to a computer program. Harari explains that emotions are the software inside the hardware, which is the human body. This software was designed in tandem by evolution and socialization to ensure our safety and success in a dangerous world.

How does it do this? Just ask yourself what happens when you become emotional. You feel. By making us feel certain things in certain situations – joy, sadness, anger, fear, disgust, frustration, surprise, love, lust, shame, pride, relief, etc. – emotions find us the most efficient and effective routes to a desirable conclusion. Think of it like you were the programmer, not the program.

If you needed to program a robot, which isn’t particularly large, strong, fast, or durable, and has nothing but primitive weapons and tools at his disposal, to survive freezing and scalding conditions, nearly impassable terrain, scant resources, and attacks from giant, ravenous predators, what would you give it?

You might decide to program a detection system for problematic weather – something that will register in the robot to seek shelter when the temperature drops or rises, or thunder bellows in the distance. It would need to be an impulse that the robot would “feel.” Perhaps foreboding?

Regarding dangerous terrain, the robot would need to sense when the environment is too treacherous to traverse, such as a mountain that is too steep, or a river that is too deep. Maybe the algorithm should feel, to the robot, like doubt?

For those times when the robot lacks resources, you might want to program into its hard drive sadness. Then, when it finally finds resources, you could make it elated. Thus, in the robot’s mind, no resources equals bad; resources equals good. Without programming, how else would it know which is good and which is bad – like really know?

Finally, when the robot comes face to face with a much larger, faster, and stronger adversary, you could program fear into it, so that the robot will run away if possible, or hide, or even fight if there’s no other option. For those instances when the robot evades attack, it would be wise to program relief – an almost euphoric relief – so that it knows this positive emotion will follow any subsequent victories.

Sound familiar? This programmer is nature, and the robot is humankind.

They Make Our Decisions for Us

But nature didn’t stop the emotional programming at that point. What separates humans from most animals and – knock on wood – all robots is the possession of self-awareness. Without conscious thought, organisms react to their surroundings based on the aforementioned impulses. It takes a developed brain to interpret these impulses as emotions (feelings), and an uncommonly developed brain to actually compete with your impulses to make the best possible decision. Human impulses aren’t always correct, which is why we became sentient: able to judge our place as individuals, as part of a larger order, and as existing at a certain point of time. Knowing this meant knowing the abstract and long-term effects of decision-making, which was hithertofore an automatic process. Humans could now understand that it’s better to save the scavenged berries for later instead of eating them at once – contrary to what their emotions wanted. This process is reason.

Scientists and philosophers had long separated emotions from reason, but contemporary wisdom states that reason and emotion work together. Social psychologist Jonathan Haidt equates the emotion/reason partnership to an elephant and its rider. The elephant is emotion, the rider reason. The rider likes to think it’s leading the elephant, and it sometimes can, but if the elephant wants to go somewhere, the rider’s not going to be able to stop it. Emotions are powerful for a purpose: an individual’s survival often depends on them.

Lots has been said about the problems of pure reason. At least at this point in human evolution, reason seems to act on emotional incentive. Emotions, replete with life-affirming positive feelings, have much to offer us that reason, operated with cold, heartless rationalization, doesn’t. Therefore, people often rationalize only after emotion had made their decision for them. We like to think that pure reason is at work when we spend a long time on a hard choice, but it’s usually the result of an ulterior motive that was concocted by unconscious processes. Emotions want you, the individual, to succeed. Reason does not always put the individual, or the group, or even humanity, first. Thus, from an evolutionary perspective, emotion is the more valuable of the two algorithms.

But rankings are always subject to change.

They are Caused by Chemical Reactions

I’ve spoken about emotions as algorithms, emotions as feelings, and emotions as ill-trained elephants. So far it’s all been symbolic. You might be wondering, then, what emotions really are. Don’t worry; they’re not figments of your imagination. They have a physical component just like everything else.

Your brain releases chemicals like dopamine, serotonin and oxytocin to make you happy. It withholds these chemicals to make you sad. It releases epinephrine when you’re angry and cortisol when you’re stressed. When you’re scared, not only does your body produce excess adrenaline, but it increases your heart rate and blood pressure.

Emotions are chemical reactions that are translated into feelings. We give these feelings names like love and nervousness and horniness, but they are the results of biological impulses unconsciously designed.

Regardless of how you define them, emotions are real and necessary for human life. Without emotions, we would have difficulty making decisions. People with damaged emotional centers, who must therefore rely on reason for day to day living, find themselves unable to make any choices whatsoever. A person can reason to no end – it’s emotion that gives reason the push in the right direction.