By Marte Rommetveit.

“I love you so much I could eat you up,” a mother might say to her child.

Chances are, the mother will be met with a confused and possibly concerned look. What does she actually mean?

To grasp this, the child needs to understand more than just the literal meaning of the words. They must comprehend the intentions behind them.

Researchers at the University of Oslo (UiO) have investigated the ways in which children develop the ability to comprehend meanings and nuances beyond the words explicitly spoken.

“The big mystery is this: How can children be skilled at comprehending many complex linguistic tasks yet interpret things completely literally in other situations?” says Ingrid Lossius Falkum, professor of linguistics and philosophy of communication at UiO.

A literal development phase

After many years of research into this puzzle of children’s language development, Falkum and her colleagues have come closer to an answer:

“We see that from around the age of four, children go through a developmental phase, a kind of literal phase, where they often take words at face value,” the language professor explains.

During this phase, children can be quite “strict”, typically lasting several years. They may be fixated on speaking correctly and choosing the “correct” meaning of a word, often interpreting your words literally, even when it does not make sense.

“I am surprised by how strong the tendency to interpret things literally is among many children,” Falkum says.

She and her research colleagues believe this prevents children from accepting expressions with different meanings.

Imagine someone saying: “John is a lion.” While an adult understands it as a compliment, meaning John is brave and strong, children in the literal phase might think you mean John is an animal.

Focused on “right” and “wrong” language

Preschool children are concerned with the idea that there are “right” and “wrong” ways to use words.

“Children are in a developmental phase where it is crucial for them to learn the meanings of words as agreed upon by the language community,” the language professor explains.

This focus can make it difficult for children to move beyond literal meanings and grasp the speaker’s intended message

“Literal meanings can be seen as the ‘correct’ way to use a word. Children are keen on following the rules.”

This literal phase does not stem from an inability to comprehend non-literal language, such as metaphors and irony.

“But the developmental phase often leads them to prefer clear and precise communication,” says Falkum.

Surprised by the finding

This challenges previous research on children and non-literal language use.

“There has been a long-standing hypothesis suggesting that children struggle with understanding non-literal language due to difficulties in adopting others’ perspectives.”

But that is not the case. The ability to understand is there, but literal meanings seem to carry more weight.

“We notice that children remain rather rigid and prefer literal interpretations for many years, provided a literal option is available,” she explains.

However, when no literal interpretation is available, children often select the meaning that best suits the context, which may involve a metaphorical interpretation.

Differences between younger and older children

The researchers conducted studies with over 3,000 children to examine how readily they accept unconventional usage of words.

What if an adult says, “Peppa Pig is in the basement.” The person is referring to the Peppa Pig book.

Five- to six-year-olds quickly interpret statements literally, even if it seems unusual for Peppa Pig to be in the basement. They justify this interpretation by reasoning that those were the exact words used by the researcher.

Interestingly, younger children appear to understand the non-literal meaning better than older children.

“Children who are a bit older start to wonder if there could be multiple meanings, and they opt for the safest one – the one aligning with what is literally said,” Falkum explains.

She notes that the authority of the adult researcher influences the situation. Because the adult stated it in a particular way, the children are inclined to believe the intention was literal.

Not all test subjects were effective

Falkum and her colleagues also tested adult participants to make comparisons in their research.

However, when they recruited a group of philosophers from the University of Oslo for irony studies, things did not go quite as expected:

“We had to stop because many philosophers interpreted the statements just as literally as the children did. It wasn’t due to a lack of understanding irony, but rather because they approached the task with a deeply philosophical mindset. Perhaps they believed someone was attempting to deceive them?”

Exploring communication with language models

A central theme in all Falkum’s research is understanding how the ability to interpret others’ intentions develops.

Currently, she is investigating how humans communicate with artificial intelligence-based language models, compared to how we communicate with each other.

“We know little about the human aspect of this type of communication. The AI revolution was striking for us because suddenly it’s super relevant to have expertise in how human communication works,” the professor says.

She believes it is essential to gain knowledge for effectively training machines and understanding how communication with them affects us. Perhaps children also interpret language models literally?

“Initially, we examined how children learn to understand others’ intentions. Now we wonder how they can understand an entity without intentions they can reason about,” she explains.

Understanding others’ intentions is a prerequisite for all communication, which should mean we cannot really understand what language models produce.

“We want to explore what happens when we attribute meaning and intentions to AI models regardless.”