The word “theory” comes from the Greek language and means “a way of reasoning or explaining an occurrence or a phenomenon in order to understand it and possibly predict it in the future.” A theory can be speculative, though it would lose credibility if it doesn’t make sense or is disproven. More often than not, there is more than one theory to explain something, and depending on one’s perspective, one of those theories would seem more plausible than the rest. Below are some such theories that make complete sense, some proven and some speculative.
1. Proportional Theory of Time
Time seems to pass more quickly as we get older because each year becomes a smaller percentage of the total number of years we’ve been alive so far.
The theory was first proposed by French philosopher Paul Janet in 1897. To put it in mathematical terms, our perception of time is logarithmic, longer in the beginning and shorter towards the end, rather than linear with each year feeling like the same amount of time. So, when you are a year old, a year is 100% of your life. At the age of eight, a year becomes only 12.5% of your life, at 18 years of age it’s 5.56%, by the time you are 35 it’s 2.86%, and when you are 98 it’s just one percent.
Another theory is that, as we grow older, the world becomes more and more familiar and we become less attentive to it with the result that time slips by. Some believe that we tend to remember things that happened between the ages of 15 and 25 more vividly than at other ages because of all the new things we experience.
There is another theory that suggests that our sense of time depends on our biological processes. There is also research suggesting that we experience time faster as our body temperature rises and slower as it lowers. Since children do have higher average body temperatures than adults, it’s possible they perceive time more slowly. (source)
2. Parkinson’s Law
The work you have expands so that it fills all the time you have for completing it. The law is often applied to describe the growth of bureaucracy in an organization.
The idea was presented by Cyril Northcote Parkinson as the first sentence in a humorous essay first published in 1955 in The Economist and later in the book Parkinson’s Law: The Pursuit of Progress. It is similar to the ideal gas law which states that gas expands or condenses to fit the size of the box in which it is put. Parkinson worked in the British Civil Service and cites examples such as the increase in the number of employees at the Colonial Office during the decline of the British Empire.
Parkinson proposed two reasons for the increase: one is that an official wants to increase subordinates rather than rivals, and the other is that officials make work for each other. He also noted that irrespective of any difference in the amount of work, the number of employees in bureaucracies increased by 5 to 7% each year.
The law has inspired several corollaries including the Stock-Sanford corollary which states that “If you wait until the last minute, it only takes a minute to do.” Another is Asimov’s corollary which states that “In ten hours a day you have time to fall twice as far behind your commitments as in five hours a day.” There is also a computer-related corollary which states “data expands to fill the space available for storage.” (source)
3. Snake Detection Theory
The reason humans are remarkably good at noticing snakes even when they are hidden or camouflaged is that the visual system of primates has evolved to do so.
Ophidiophobia, or fear of snakes, is among the most common phobias humans experience, with over 50% of people having dreams about them. According to anthropologist Lynne Isbell, snakes have evolved to be difficult to immediately be noticed. But, the dangers that poisonous snakes posed to primates created predatory pressure for millions of years that favored those with specialized visual systems.
The individuals who successfully detected the snakes and survived passed on their instincts or skills to their descendants. Compared to other mammals, primates have a disproportionately large and effective pulvinar region, the part of the brain that visually detects or notices required objects. So, in a way, according to the theory, snakes were responsible for the advanced sensory interface with the external environment among primates. (source)
4. Monsters Under the Bed Theory
The fear among children that there might be a monster under their bed is a remnant from hunter-gatherer days when children had to fear for their lives due to wild animals if they were to sleep alone.
According to Peter Gray, professor of psychology at Boston University, infants and young children who cried and screamed when left alone at night were more likely to have attracted an adult’s attention and survived when faced with a wild animal threat. The children who survived due to that fear would pass on their genes to their descendants. Though in the modern world there are no real threats while sleeping in the dark alone, that remnant evolutionary instinct kicks in and the children cry, seeking the safety adults can provide.
According to child psychologist Laura Kauffman, since children don’t yet have experience coping with the sounds or the silence at night and their imagination is quickly expanding, they are particularly prone to fearing the unknown. They project that fear as the bogeyman or monsters under the bed. Separation anxiety could also be a reason for the fear which is why getting into bed with the parents helps them sleep better. (1, 2)
5. Horseshoe Theory
The political spectrum isn’t a straight line but horseshoe shaped. The far-right and far-left wings are more similar to each other than the moderate left and right.
The theory is attributed to French philosopher and writer Jean-Pierre Faye who mentioned it in his 2002 book Le Siècle des ideologies though the idea that far-left and far-right are similar dates as far back as the 1970s. The proponents of the theory also point out how the extremes tend to gravitate towards authoritarianism or totalitarianism.
The horseshoe theory, however, is not currently supported in academic circles as it is considered an oversimplification of political ideologies. It has also been criticized by people from both ends for grouping them with their polar opposites. (source)
6. IKEA Effect
A cognitive bias in which people place a higher value on something they partially created, like the self-assembled furniture from IKEA.
The effect was identified by Michael I. Norton of Harvard Business School, Daniel Mochon of Yale, and Dan Ariely of Duke. Their studies were based on products such as Build-a-Bear which lets the buyer make their own teddy bears. It is more expensive than a teddy bear and saves the manufacturer production costs. Another study was on the popularity of “haycations” that allow people to pay money to work with farmers instead of getting paid for the work.
Norton, Mochon, and Ariely also conducted experiments in which participants would build Lego items, origami figures, and assembled IKEA boxes. The results they got suggests that people who build something themselves value it more than something they were not required to build, even though they do a poor job. (source)
7. The Peter Principle
A concept according to which companies promote employees into management posts based on their performance rather than their ability until they cannot perform that well anymore resulting in incompetent and inefficient managers.
The concept was developed by Laurence J. Peter and published in the book The Peter Principle by Peter and Raymond Hull in 1969. Though originally published as a satire, it gained serious recognition for presenting the shortcomings in the way people are promoted in a hierarchical organization. According to the principle, “In a hierarchy, every employee tends to rise to his level of incompetence.”
When someone competent at their job is promoted to a new role that requires different skills, they may or may not be as competent. If they are not competent, they would not be promoted again, and if they are, they would be promoted to another new role. They will keep receiving promotions until they are not competent anymore and will be stuck in that role for the rest of their career, a situation termed “Final Placement” or “Peter’s Plateau.” This leads to Peter’s Corollary which states that after a certain time in a hierarchy, every post will be occupied by an incompetent employee. (source)
8. Black Swan Theory
The idea that rare, catastrophic events which seem unexpected or highly unlikely but are rationalized in hindsight, play more of a major role in history than the predictable events.
The term “black swan” was used by the second-century Roman poet Juvenal to describe something that doesn’t exist. But in 1697, when Dutch explorers led by Willem de Vlamingh went to Western Australia and saw black swans, it changed the meaning of the term to something believed to be impossible but that later would be disproved.
The black swan theory was developed by Lebanese-American scholar and statistician Nassim Nicholas Taleb to explain the disproportionate role of large, rare events that are beyond the realms of expectations, the impossibility of calculating the probability of the rare events, the psychological biases of people that blind them to the uncertainty, and the massive role those events play. According to Taleb, all major scientific discoveries, artistic accomplishments, and historical events are black swans, and he gives examples such as World War I, the fall of Soviet Union, 9/11 attacks, the Internet, and computers. (source)
9. The Cheerleader Effect
People seem more attractive when in groups than when they’re alone.
The term was coined by the character Barney Stinson in the TV show How I Met Your Mother in the episode “Not a Father’s Day” when he points out to his friends a group of women who seem attractive at first but look ugly when seen separately. It was also observed later in the episode by Ted and Robin who notice the same about Barney’s friends.
The idea was proven right in several studies by Drew Walker and Edward Vul in 2013 as well as by van Osch et al. in 2015 in which participants rated men and women seen in a group photo and seen in an individual photo. The effect, however, occurs only in same-gender groups, both small and large. The proposed explanation by Walker and Vul is that the human visual system averages out the unattractive traits as it takes “ensemble representations” of the faces. The explanations offered by van Osch et al. are that it is either because of selective attention to attractive group members or the Gestalt principle of similarity. (source)
10. The Dunning-Kruger Effect
A cognitive bias in which people of low ability tend to assess their ability to be greater than it actually is.
Social psychologists David Dunning and Justin Kruger identified the phenomenon in their study Unskilled and Unaware of It: How Difficulties in Recognizing One’s Own Incompetence Lead to Inflated Self-Assessments. They derived it from the criminal case of McArthur Wheeler who robbed banks after applying lemon juice on his face as he believed it would make his face invisible to the surveillance cameras.
Though the phenomenon was published in 1999, it was mentioned by Confucius, Socrates, William Shakespeare, and other intellectuals throughout history. Dunning and Kruger tested their hypothesis on undergraduate students by examining their skills in logical reasoning, English grammar, and personal sense of humor, and then asking them to estimate how they scored. While the competent ones underestimated, the incompetent ones overestimated.
In a further 2006 study, Skilled or Unskilled, but Still Unaware of It: How Perceptions of Difficulty Drive Miscalibration in Relative Comparison, the perceived difficulty of the tasks was manipulated. The result was that with moderately difficult tasks there wasn’t much difference in the accuracy of performance estimations made by the best and worst performers. But, with difficult tasks, the best performers’ estimations were less accurate than that of the worst performers. The study, however, failed in Japan as Japanese tended to underestimate their abilities suggesting that cultural influences are a factor. (source)