LONDON — He reads fluently (while wearing a Gruffalo costume), he does math with ease and he can explain scientific concepts such as how rain forms.
He is also 3 years old.
The toddler, Muhammad Haryz Nadzim, was invited last week to join Mensa, a British society whose membership rules require an I.Q. in the top 2 percent of the population.
Haryz, as his family calls him, received an invitation to the society after meeting with a consultant psychologist who assigned him a score of 142 using the Stanford-Binet intelligence test. Scoring above 145 is considered “genius or near genius,” according to the test’s website.
The 3-year-old is now Mensa’s youngest current member, the society said in an email on Wednesday. The youngest-ever member was age 2 years 4 months at the time of joining.
Haryz’s mother, Nur Anira Asyikin, said on Instagram, “My mini brainbox just got invited at his little age to be part of Mensa,” and congratulated her “very very clever” son.
Mensa was formed in Oxford, England, in 1946 by Roland Berrill, an Australian lawyer, and Lance Ware, a scientist and lawyer. It has more than 110,000 members across the world.
Meeting the membership criteria usually means taking an I.Q. test supervised by the society. For children under age 10 and a half, Mensa says on its website, an assessment by an educational psychologist must be made. That report is then submitted as evidence to support membership, as happened in the case of Haryz.
Ms. Asyikin could not be reached for comment on Wednesday, but she said in a CNN report that her son was “very much your typical 3-year-old,” adding that he particularly enjoyed playing with modeling clay and toy bricks. Ms. Asyikin is an engineer and the family lives in Durham, in northeastern England, according to CNN.
An Instagram page dedicated to Haryz’s exploits includes a video of the youngster reading books, including “The Gruffalo,” by Julia Donaldson, singing nursery rhymes, and — just before his second birthday — recounting the story of the Gingerbread Man.
In a video posted on his Instagram profile on Tuesday, Haryz does simple mathematics: “Two plus six equals eight,” he tells the camera, drawing numbers and symbols in the air.
Ann Clarkson, a Mensa spokeswoman, said in an email on Wednesday that a high I.Q. was “like a toolbox — it gives children the equipment to learn, but they still have to put in the effort and practice to become expert at something.”
Though all children are unique, she said, what makes Haryz different is “his ability to learn very quickly and process information fast.”
Child prodigies have long caused admiration and interest. Alma Deutscher, from Austria, was composing piano melodies at age 4 and played Carnegie Hall in New York in December at age 14. In Belgium, Laurent Simons, a 9-year-old, was on course last year to become one of the youngest people in the world to graduate from a university.
But the pressure that comes with such gifts can take a toll in the long term.
Saul Chandler, a former violin prodigy who played Carnegie Hall twice before age 13 and suffered a nervous breakdown by 16, told The New York Times in 2018, then age 70, that if he could forget music, he would.
“They turned me into a trained monkey,” he said, adding that he would not want to be remembered for his childhood achievements. “Because I ended up doing a lot of other great things in my life, too.”
Despite her obvious delight in Haryz’s talents, Ms. Asyikin hinted at the pressures in an Instagram post.
Whatever her son went on to achieve, she wrote, “we will always be proud of you.”