Cake or ice cream? Researchers dish on why kids often choose 'both'

Children may not be messing with you when they refuse to choose between one of two options, say researchers, noting that the youngsters may simply be confusing the word "or" with "and."

'The child may interpret things slightly different than you intended it, and they are not being disobedient'

New research indicates children can have a hard time distinguishing between the words 'and' and 'or,' making it difficult to choose between things. (Ian Barrett/Canadian Press)

When Andrea Astle-Rahim would offer her then four-year-old stepdaughter a choice between cake or ice cream, the child's answer was often perplexing: "Yes, please!"

Given a choice between two items — whether delicious or not — time and again, the child would select an option Astle-Rahim didn't think she was putting on the menu: both.

Studies dating back to the 1970s have suggested young children have trouble distinguishing "or" from "and." Now, three researchers at Ottawa's Carleton University, including Astle-Rahim, and two at the Massachusetts Institute of Technology have come up with a conclusion about where the mix-up occurs in the thought process.

Short answer for parents: Your kid is (likely) not just messing with you.

"In certain cases, the child may interpret things slightly different than you intended it, and they are not being disobedient," lead author Raj Singh told Robyn Bresnahan, host of CBC's Ottawa Morning.

Cake or ice cream? Both, please! (Ian Barrett/Canadian Press)

Adults strengthen understanding by tests

The process children go through to make that determination is similar to the one adults use, but children are just missing one step, said Singh, a professor of cognitive science at Carleton.

When adults infer meaning from words and the sentences they hear, they figure it out using "scalar implicatures" that help them evaluate what is said and strengthen their understanding of what it means, often by comparing it to other statements, Singh said.

With the phrase "The man is holding a fork or spoon," an adult might ask three questions: Is he holding a fork? Is he holding a spoon? Is he holding both?

"When I say something like, 'The man is holding a fork or a spoon,' it literally means he is holding one or the other and possibly both," said Singh. "But we [as adults] often take the speaker to be implying that the man is not holding both; he is holding just one or the other."

This interpretation comes from comparing the statement to one where "or" is replaced by "and," and reasoning that if it were "and," it would have been illogical for the speaker to have said "or."

Similarly, adults might conclude from the statement "John ate some of the cookies" that John did not eat all of them, even though, technically, "some" could mean "all."

But the researchers found that while children do consider some of the options when trying to interpret sentences, they skip this last step.

Kids tested at Ottawa daycare

The researchers tested 59 English-speaking children at a daycare. They ranged in age from three years and nine months, to six years and four months. The researchers also tested 26 adults.

Astle-Rahim said the children were introduced to a puppet (named Fuzzy) and a picture book that had pictures of characters holding various items. Fuzzy would then describe a picture and the children would determine if what Fuzzy said was accurate.

They found children, like adults, ask themselves if — to use the previous example — the man is holding a fork, and if he's holding a spoon, but that's as far as they go.

"If the man was holding just the fork and you say, 'The man is holding a fork or a spoon,' [the children] say that's a bad description," he said. "If the man is holding both fork and spoon, and you say, 'The man is holding a fork or a spoon,' they accept it as a good description."

"[A child is] a remarkable little creature; it's basically the adult, it's got the meaning of the word, it's got this fancy machinery. It just in this particular case happens to spit out the opposite of the adult inference," he said.

Children grow out of it 'pretty soon' after age 6

Singh said he suspects, based on what cognitive science researchers know about the development of children, that children figure out the difference between "and" and "or" pretty soon after the three to six age range they studied.

Astle-Rahim said she wishes she had been armed with the research sooner.

"It would have allowed me to respond differently as a parent," she said. "Now I would know she genuinely thought both options were being presented to her, and rather than telling her to stop being silly, I would have said no, no ... pick one."

The other co-authors of the study, being published in Natural Language Semantics, an international peer-reviewed journal, are:

  • Deepthi Kamawar, an associate professor of psychology at Carleton University.
  • Danny Fox, a professor in language and thought at MIT.
  • Ken Wexler, an emeritus professor of psychology and linguistics at MIT.


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