Signs of low intelligence

© January 2024 Paul Cooijmans


"Low intelligence", in this article, refers to the intelligence range where independent societal functioning is hindered significantly by the individual's lack of mental ability. Traditionally, an I.Q. of 70 was quoted as the threshold for such, but in the later twentieth century this was raised to 85 in some countries. The usual explanation for this change is that (Western) society has become more complex and mentally demanding, but an alternative possibility is that people have become stupider and the norms adapted to that, so that an I.Q. of 85 now represents the level that used to be called 70. In case the decline of raw intelligence continues, ever more people will reside in the range defined in the first sentence of this paragraph, whichever I.Q. number is used to mark the threshold. At the current apparent rate of decline, this group will constitute the majority of the Western population by the early twenty-second century, with profound societal consequences. These consequences are not obvious to many, due to the political-ideological denial of the societal relevance of intelligence.

Because of this general taboo on intelligence differences between individuals and the societal relevance thereof, and especially the taboo on the societal relevance of low intelligence, one may well be unaware of the low intelligence of some persons in one's environment. Low intelligence is rarely made explicit, but hidden under euphemisms like "learning disabilities", diagnoses of supposed rare disorders, or even called some variant of "giftedness" (that last concept is almost devoid of meaning these days). While the intention behind this obscurantism may be good — exempli gratia, avoiding embarrassment of the lowly intelligent individual — it has resulted in ignorance regarding the outward presentation of low intelligence. To repair this state of affairs, below is a list of signs or features one may observe in lowly intelligent individuals, with explanation where needed.

It is not claimed that each lowly intelligent person possesses all of these features, or that someone is lowly intelligent for merely displaying one of them. Neither is this list claimed to be complete. But an individual engaging in multiple of the below behaviours is likely of low intelligence. The source of the information in this essay lies in decades of personal observation of thousands of people from all over the spectrum of mental ability. These observations are objective, never ironic and never meant to ridicule particular persons. This paragraph aims to prevent the usual avalanche of "Do you mean me?" responses that tends to follow articles on sensitive personality-related topics.

Signs of low intelligence

Inability to retain information

Retaining information is done by comprehending that information and connecting it to other pieces of information already known. Thus it is anchored in memory and able to be retrieved later. Persons of low intelligence are not well able to comprehend and interconnect information, and thus they are bad at retaining or remembering information in real-life situations, and will distort the information when attempting to retrieve it, or even lack any memory of it at all. This makes them unreliable witnesses; when questioned about an event, they will provide sharply different (distorted) versions of it on different occasions.

The above is not about "rote learning" but about real-life functioning. It is not claimed that low intelligence precludes rote learning. In fact, some persons of low intelligence may be good at narrow abilities like rote learning or mental arithmetic, but their lack of general intelligence will prevent them from putting those skills to meaningful use in the real world.

Asking or saying the same things on subsequent occasions

When meeting a person of low intelligence frequently, one may observe the person to ask or say things that the person has already asked or said on many prior occasions. This is a result of the aforementioned inability to retain information; the person is not aware of having said or asked those things before. While that information may be stored in the person's brain somehow, it is there in a way that makes it not readily accessible for real-life purposes, probably due to a lack of interconnectedness and comprehension.

Not understanding explanations

Persons of low intelligence can not understand matters beyond a modest level of complexity, even with repeated explanation. Not only do they not understand the explanation no matter how often it is repeated, but every time the explanation is given, it appears to them as if they are hearing that explanation for the first time. This is because they have no memory of the earlier attempts at explanation, which in turn is because they could not understand it and could not connect it to any other information, and thus it was not retained.

Asking someone who has one's mouth full

A person of low intelligence may ask you a question while you are eating and have your mouth full, for the person does not realize that you can not answer in that state. A person of low intelligence can not mentally place oneself in another's position. This can be generalized to any other states and positions that render you unable to respond.

Frequent complaining

Persons of low intelligence are not good at solving problems. Therefore they tend to have many unsolved problems, about which they may complain repeatedly and conspicuously, hoping that someone will solve their problems for them. Alternatively, their complaining behaviour may take the form of projection; with remarks like, "How far are you behind with the rent?" or "Can you still afford your football tickets"? they inadvertently reveal their current concerns. This is not a deliberate strategy, it is more that they are involuntarily and unawarely assuming their own problems in others.

Interrupting the speaker or not listening

Persons of low intelligence have difficulty paying attention to what another person is saying, and may interrupt the speaker frequently with random interjections. This results from their short attention span and lack of impulse control, as well as their inability to comprehend. It may be noted that this form of impatience differs from the impatience that is sometimes attributed to intelligent individuals faced with someone who is not as quick to understand as they are; the latter is more a sort of boredom.

Watching you instead of the event

While watching television or whatever visual display together with you, persons of low intelligence may watch you instead of the film or program, and ask you what is going on in it. They are not well able to comprehend what they see with their own eyes and may prefer to rely on another viewer to tell them.

Using idioms

Persons of low intelligence are not capable of abstraction, but have concrete minds that perceive the world in coarse chunks that are not further analysed. As a result, they do not formulate their utterances from the ground up using abstract thought and logic, but simply repeat expressions (chunks of language) they have heard others use in pertinent contexts. This mode of expression tends to be non-literal, idiomatic, chunked. The idioms are like black boxes to them; they are not aware of (the absence of) possible meaning or logic in such a linguistic chunk of words, and thus do not realize that the person they are talking to may not know this particular idiom and may have no way of deducing its meaning from its constituent words. This use of idioms is like cooking from tin cans, while abstract-logical communication is like cooking from the ingredients.

Displaying socially or emotionally inappropriate behaviour

Some aspects of social-emotional interaction are part of the cognitive domain and therefore not well understood by persons of low general intelligence, who may thus display inappropriate responses such as laughing in, or about, a sad situation. This is different from the inappropriate behaviour sometimes attributed to persons of normal or higher intelligence who are said to "miss non-verbal cues".

Violating moral principles

Persons of low intelligence may violate moral principles like "treat others like you would want to be treated", or whichever formulation of the Golden Rule. This results from their inability to understand such principles, which, like everything righteous, are logical in nature and demand a certain level of intelligence to be understood. They are not able to be righteous from within and require guidance and enforcement, ultimately through physical force, to keep them from committing crimes. The majority of criminals have below-average I.Q.'s.

Becoming aggressive and violent

Some lowly intelligent individuals become aggressive and/or violent when contradicted or otherwise dismayed. This relates to a lack of impulse control, and violent crime peaks in the I.Q. range from 80 to 90. This concerns males more often than females.


Persons of low intelligence are easily tricked into believing falsehood, as they are not able to distinguish between truth and untruth.

Indulging in unhealthy habits

Persons of low intelligence are at an elevated risk of entertaining unhealthy habits to an extreme degree. Typical examples are smoking, overeating, recreational drugs, anabolic testosteroids, invasive cosmetic procedures, physical inactivity, or spending much of the daytime in bed. This has to do with the lack of impulse control and poor ability to delay gratification that are inherent to low intelligence.

Making debts

Persons of low intelligence are at raised risk of getting in debt by spending too much, buying in instalments or other forms of borrowing, playing in lotteries or other forms of gambling, pornography and/or prostitution, and so on. They do not understand that buying in instalments is a form of borrowing and that one is thus paying much more than when paying cash, and do not understand that gambling games will almost necessarily result in a net loss for the gambler in the long term. It is quite common for low-I.Q. people to have a curator or trustee to take care of one's financial business and administer one's bank account. It is difficult for them to be frugal or economical, because such requires a minimum level of intelligence.

Electronic mail behaviour

In the past, the use of computers, Internet, and electronic mail required a moderate level of mental ability, but over the first two decades of the twenty-first century this requirement dropped significantly with the rise of smart telephones and increasing user-friendliness of online services. As a result, persons of low intelligence have become frequent users of electronic mail and other Internet-based communication systems, and observations can be made regarding their electronic mail behaviour.

First, the mere fact that an electronic mail message originates from a smart telephone, as betrayed by inserted additions at the bottom like "Sent from my…", is a moderately strong indicator that the sender is not too bright. This may offend some people, but we have to be honest about this unmistakable observation.

Then, a person of low intelligence may send you multiple messages in rapid succession without awaiting an answer, possibly modifying or adding to the previous messages in each following message and not having the patience and respect to let you reply first.

Such a person may also write in all lower case, without punctuation, and without structuring one's message in paragraphs, so that it appears like one solid block of text.

And the person may use expressions like "good morning" or "good evening", thus revealing a misunderstanding of the nature of electronic mail, which, after all, may be read by the receiver at any time of the day. Lowly intelligent individuals may not realize this fact and be under the impression that their message is read the instant they send it, as with an instant messaging system.