Do you have free will? A question that’s haunted one too many philosophers. As a society and as an individual, we tend to unhesitantly think, “Yes! I can choose the way I live.” Not only is it natural for us to think that way, but there’s a sort of comfort in believing we have the luscious ability of free will. As an individual, you could find stability in that wonderful feeling of independence: the belief that your life is in your hands and you’re the one in the driver’s seat. As a society, you could blame individuals for their choices, like “Oh, the planet’s dying? It’s obviously because the people aren’t recycling enough! They’re not being responsible”.  Of course, they always talk about responsibility. But the truth is, our free will is heavily biologically and environmentally constrained– to the point where we can begin to doubt whether we have any at all.

As an example, we’re going to take a murder, and look closer at the stuff going on in his brain seconds to millennia before pulling that trigger. Simply understanding how neural signals trigger muscle action doesn’t tell you the story behind the act– did the person think it was an act of bravery, or an act of malice? Context is everything. If we’re going to understand the complicated acts of violence, we need to study them in layers: what happened a second before in his brain, what happened minutes before, what happened in childhood . . .

If we’re starting at the activity of a person’s brain a second before they pull the trigger, we must start at the amygdala. Simply put, the amygdala controls fear. Evolutionally, it is vital because if you spot a tarantula, your amygdala will react way before your visual cortex or frontal cortex can even process it, allowing you more time to run. But there’s two faults, the amygdala is highly inaccurate and makes you act before your frontal cortex can take a logical approach on your action. The insular cortex activates when things seem immoral… but also when you see something different or out of the common.  For humans, the insula tends to believe that what is different is morally disgusting, and then tells the amygdala about it. The amygdala listens, and starts to fire, making you act impulsively. And though the frontal cortex is known for making you do the hardest thing when it’s the right thing–like gratification control, long-term planning, etc.– once you start doing something impulsive, the frontal cortex then starts helping you in the action. So, the question becomes, did the murderer have a choice in what went on in his brain? Could he control his amygdala level and insula activity a few seconds before pulling the trigger? The truth is simple. No.

Now, we begin to go slightly further back in time. A few minutes before committing murder, what was his environment like? This might sound completely irrelevant, but it is entirely overlooked. Your sensory information, even if it might be unrelated to your actions or values, are constantly affecting the activity in your brain and the choices you’re making. In Robert Sapolsky’s The Biology of Humans at Our Best and Worst lecture at Stanford Iranian Studies Program, he states that if you're sitting in a room being assessed on your political opinions, and there is smelly garbage in that room, you're statistically more likely to be a social conservative. Additionally, if on a wall you see a painting of two creepy eyes looking at you, you’re more likely to act generously. The list goes on. If right before a trial, a judge was eating lunch, he's more likely to allow a prisoner to be on parole. And in a brain scan, if someone starts flashing a bunch of photos, and one of them is a person from a different race, the amygdala immediately flares up. Though cliche, the simple fact is that as humans our choices are imprisoned by external stimuli– we are extremely vulnerable to the environment.

A few seconds before the act, the focus was purely neuroscience. A few minutes before the act, the focus was on external stimuli. A few hours to days before the act, the focus is on hormones, and how they affect one’s probability towards violence. Though testosterone is the hormone of aggression, it doesn’t invent aggression; it magnifies pre-existing social patterns of aggression. If you gave humans a shot of testosterone, they would do whatever is necessary to maintain their social status. If that human was a buddhist and you gave them a testosterone boost, they would start to increase the amount of generous offers they give. But, since most humans defend their status through aggression, testosterone acts in violence rather in generosity. Another misunderstood hormone is oxytocin, famously known as the love hormone. The sight of your pup releases oxytocin; the feeling of your mother’s warm hug releases oxytocin, etc. Oxytocin is imagined to be the hormone in charge of all the good traits– love, generosity, cooperation, empathy. It’s even associated with better listeners or higher emotional intelligence. Essentially, oxytocin is supposed to make us more pro-social. However, it’s with a catch. Oxytocin enhances the feeling of Us vs. Them, making us pro-social, but only to people we believe feel like us. In fact, oxytocin makes us treat people different from us, worse. If you ask people about the runaway trolley paradox, and you assign names to the victims, people are less likely to choose to kill a person with the name of someone with your race and are more likely to kill a person with the name of someone that is from an “enemy” race, like Adolf or Muhammad rather than Adam or John. Hence, our hormones increase our probability of violence and subconsciously chooses for us, who we are violent to.

Moving even further back in time, we go back to adolescence. In adolescence, our dopamine system is fully developed, but our frontal-cortex is only half grown, and won’t fully grow until you’re about twenty-five. This explains why most adolescents are impulsive and have a strong desire to fit in. Since our frontal-cortex is the last part of our brain to fully mature, it’s the part of our brain that the environment impacts the most. During your late adolescence and early adulthood, your environment has a huge impact on your frontal cortex. Certain genes associated with certain traits only become those traits in certain environmental circumstances. The same genes can have different outcomes in different environments. How you become is the effect of the interactions between your gene and the environment. For instance, in Robert Sapolsky’s talk, he shows that the gene 5HTT is associated with depression– but that only happens if you have childhood trauma. The gene FADS2 is associated with higher intelligence– but only if you’re breast fed. The gene MAO-alpha is associated with antisocial, violent behavior, if you had childhood abuse; with criminality, if you have high testosterone levels; and with economic competitiveness if you have high stakes. This shows that your experience in adolescence affects not only the development of your prefrontal cortex but also which way your genes play out.

If we go a millennia back in time to our ancestors, we see how their culture shaped who they were and who you are even now. Millions of years back, there were pastoralists, who were more vulnerable to robbery than other groups. If you were a hunter gatherer, nobody can just steal the rainforest. If you’re an agriculturalist, nobody can steal twenty acres of land in one night. But, if you’re a pastoralist, people can steal all your herds in a few hours. Therefore, pastoralists came up with cultures of honor, violent retributions, honor killing, and warrior classes that still live on many generations later. Additionally, most of our behavior evolved from three ancient, fundamental concepts: individual selection, kin selection and reciprocal altruism. Simply put, individual selection is basically where organisms try to leave as many copies of their genes as possible. Kin selection is where organisms help their relatives maximize reproductive success. And reciprocal altruism is the idea where we will do a service or give you a good, but only if we know that you will repay me: reciprocal relationships of cooperation. The latter concept is what developed the idea of economy, money, and trade. Though there are some differences–like families with kids adopted from all parts of the world, and random acts of kindness committed without the intention of the receiver repaying you–on a broad scale, we can easily see how people’s actions fall into these three categories. Beliefs from thousands and millions of years back still have strong lingering effects on people to this day.

Looping back to the person who just committed the murder. After analyzing his life seconds to millions of years before he pulled the trigger, we can see how truly complicated it is to understand someone’s behavior, let alone judge someone because of it. But going back to the question we started with, did the murderer have the choice to not pull the trigger? Could he control his amygdala? What about the external stimuli, or his testosterone levels? What about his experience during his adolescent years that affected his frontal cortex and his gene variant? Maybe his ancestors were pastoralists? I say that if he had a choice in pulling the trigger, it was overwhelmingly dominated by things out of his control. And perhaps, our entire life, and the life of others are never really under our own will, despite the deception that it is. So, what do we do?