Aggression is an act, carried out towards another person intentionally and without the permission of the victim. Many people believe that we are naturally born with this reactionary act, while others believe that it is a learned response from our culture. There of course is hundreds, maybe even thousands of studies proving each conflicting theory. So whether it is nature or nurture, scientists have agreed there are many causes to aggression, which will include inner, interpersonal and external categories.
Inner causes of aggression has been named and categorized into five different types. The first category is frustration. “They defined frustration as blocking or interfering with a goal” (Bushman & Baumeister). This is one cause of aggression that most of us know too well, the type we show earliest. As toddlers, children will get aggressive with each other quickly over any frustration that they are feeling. To me, this is the most powerful inner cause of aggression because to have something in the way of a goal will cause inner turmoil, that will result in action. Any action that will let you achieve your goal.
Bad moods are another cause of aggression that will come from inside a person. People are far more likely to get aggressive as a way of handling a situation, when they are already irritable about another unrelated issue. Suppose you just broke up with your boyfriend and then someone knocks into you knocking you down accidentally. You would be more likely to want to yell or hit that person if you are in a bad mood, as opposed to if you were in a good mood from a previous event.
Hostile cognitive biases are the way we perceive ambiguous and even innocent actions of others. We are more likely to act aggressively, if we view actions as aggressive from others. The bias that ambiguous actions are hostile, is hostile attribution bias (Baumeister & Bushman). Perceiving all social interaction as aggressive would be a hostile perception bias. If you expect hostility from others, this is a hostile expectation bias. So in general, if a person perceive people or the world at large as hostile, they are more likely to react with hostility as well.
Age is another cause of aggression. The most hostile and aggressive age for human is childhood, namely toddlers. Toddlers will resort to violence 25% of the time when faced with a problem, much higher than any other age group (Baumeister & Bushman). Adolescents and young adults come in second on the aggressiveness scale, partly the reason why so many murderers are in this age range. A toddler then, has a better chance of hitting you for taking something away from then, then any other age group.
A person’s gender may also be the cause of aggression, men of course, are statistically more aggressive. I am sure it has a lot to do with the natural makeup and chemical compositions of their bodies. “There is no known society in which women commit most of the violent crimes” (Baumeister & Bushman, 2013). So from childhood, men will be far more likely to be aggressive in all stages of life and age, just because they are men.
Beyond inner causes, there are also interpersonal causes attributed to aggression as well. The first sub-category is selfishness and influence. This purports that people are aggressive as a way to get what they want. If a child throws a fit and yells, and is then rewarded with his goal, he will continue the process. So if it works, it will be a method that is used up until and including the years of adulthood.
Domestic and relationship violence is an epidemic in many cultures, ours included. “Aggression is highest amongst siblings, as compared to all other relationships (Wiehe, 1991). This cause of aggression includes child abuse, molestation, as well as spousal abuse.
External causes of aggression are more controllable, as far as how much the influence will affect a person. Weapons effect is a term for the aggressiveness of people around weapons. People are far more likely to be aggressive towards someone holding a gun, then a phone. Even when not in danger, studies have shown that people tend to react more aggressively while in the same room as a weapon, as opposed to a benign item.
Mass media is a huge influence, most notably, our youth. When people watch violence, they act more aggressively. Same thing goes for games and the like.
Unpleasant Environments cause aggression. Ever been working and sweating outside, had someone cause pain by accident and you have to stop yourself from punching them in the face? Well you are not alone. “Time period studies generally have found higher violence rates in hot years, hot seasons, hot months, hot days” (Baumeister & Bushman).
Chemical influence, drugs, can cause aggression. Most notably would be steroids, which cause infamous “roid rage.” Alcohol or a lack of serotonin can also be a cause of aggression in people. Within the External category of causes, chemical influence is the most powerful cause, just think of how many people are on pills to alter or change their body’s chemical makeup to stop anti-social behavior.
So while there are many, many causes of aggression and scientist can hardly agree on anything concrete, they can agree that it is an anti-social behavior. While many will argue that it is pure nature that causes our aggressive behavior, one can see that as a person gets older, society indoctrinates the need for less aggressive behavior.
Baumeister, R. F., & and Bushman, B. J. (2011). Social Psychology and Human Nature, 2nd e.d. Wadsworth: Cengage Learning.