Is Psychology just common sense?

When I tell people I’m studying psychology, one of the reactions I sometimes get (mainly, I’ve observed, from older people) is confusion: many seem like they can’t see the point of psychology as a subject. In this case, they will often say psychology doesn’t need to be studied as it is just “common sense” (something I apparently have nowhere near enough of).

Although I haven’t yet tried it, an easy way around their confusion could be to just asking them what common sense actually is, because it’s surprisingly difficult to get an agreed-upon definition.

My textbooks didn’t help me much here, so I Googled it. One definition was that common sense is “the basic level of practical knowledge and judgment that we all need to help us live in a reasonable and safe way”, which seems to make sense.

Looking at this, it’s understandable why people think psychology is common sense; in normal life we need to have some idea of how situations will unfold, and how both ourselves and others will normally behave (sounding familiar?).

However, most people haven’t been taught that we don’t have a true knowledge of any of this; we don’t perceive the raw truth, but we perceive everything through a set of biases – like being born wearing tinted glasses and never knowing they are tinted.

Annoyingly, most of the people saying psychology is common sense are also the people least likely to believe you when you try to explain that.

So, where do common sense and psychology agree and disagree?

One area of contention is aphorisms (familiar sayings). People often express common sense by familiar sayings, for example, “the grass is always greener on the other side”. However, these sayings are often contradictions e.g. “absence makes the heart grow fonder” vs “out of sight, out of mind”….

The difference between psychology and common sense is that psychology, instead of letting the contradictions coexist, sees them and tries to test them. Here are some “common sense” sayings, along with psychological studies on them:

1) “You can’t judge a book by its cover”
Well, people kind of can. A study in Japan used a personality test to find the most selfish (egoists) and least selfish (altruists) people in a sample. University students were then shown 30-second long silent film clips of some of these people, and were asked to guess how altruistic they were. Sounds difficult, especially seeing as they didn’t even get to hear what the people on the clips were talking about, which might have been a good clue. However, the students were correct the majority of the time, so they could judge a book by its cover.

2) “Birds of a feather flock together” vs “opposites attract”
An American study on recently-married couples found that having similar personalities was correlated with a happier marriage, but there was little effect for values and beliefs. So, birds of a feather flock together seems to be true, when it comes to personalities at any rate. In terms of friendships, another study found that women tend to pick friends who were of similar attractiveness to them.

3) “Two heads are better than one” vs “too many cooks spoil the broth”
A few studies have found that people doing tasks in groups will each put in less effort than they would individually (known as Social Loafing), so the second phrase looks more likely to apply. However, another found that people teaming up to do a pattern-finding task would perform much better than any individual person could, as long as they were roughly equal in skill – if one person was incompetent or could not explain their ideas, the term were not better than individuals.

There is actually a branch of psychology that focuses on common sense, known as “folk” or “naive” psychology, which focuses on how people use psychology, and psychological terms, in daily language. While normally criticised for not being scientific, it uses basic forms of things scientists use, such as heuristics and inductive reasoning, so the folk psychology way of thinking about specific ideas could just be the precursor to the scientific way rather than against it. So, even though people have a flawed understanding of how they work, it doesn’t mean they shouldn’t try and make sense of it anyway.

P.S– Just thought I’d share my mum’s quote about the idea of academically smart people with no common sense: