Young Sheldon provides additional context as to why Sheldon loved to mock Howard in The Big Bang Theory. Despite the main CBS sitcom ending in 2019, the socially-inept genius' story continues through the prequel series, which chronicles his years living with his family in Medford, Texas. Now in its fourth season, the series tackles Sheldon's first year at East Texas Tech.

While qualifying to go to college at an early age was easy for Sheldon, taking the opportunity was not easy. Mary was hesitant about the idea despite prestigious universities like Princeton and CalTech expressing their interest to take in her son. After coming up with a compromise to go to a smaller but closer school like East Texas Tech, the Cooper matriarch eventually agreed. Despite Sheldon going to a lesser-known college compared to his friends in The Big Bang Theory, he lorded over them; not missing any opportunity to boast about his superior IQ. He was particularly mean to Howard, however; aside from being the only one from his group of friends who doesn't have a doctorate bar Penny, Sheldon also liked to look down on his profession as an engineer.

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Young Sheldon season 4, episode 10, "Cowboy Aerobics and 473 Grease-Free Bolts" provides additional context on exactly why Sheldon dislikes engineers. After practically begging to be Dr. Linkletter's lab assistant, the young genius was excited about actually helping the professor with his theories. So he was sorely disappointed when he found out that being a lab assistant didn't really give him any say on whatever Dr. Linkletter was working on; instead, he was tasked to scrub the grease off from hundreds of bolts. Sheldon described this as a "tedious menial job to be performed by a monkey or worse, an engineer." This explains how, at a very young age, he attributed Howard's profession to mind-numbing work - something that doesn't require much thinking and since his best asset is his brain, he couldn't really impose on his intellect.

Howard Wolowitz at the International Space Station in The Big Bang Theory

This idea stuck with Sheldon until he grew older, so when he met Howard, who's an engineer, he made him his easy prey. He demeaned Howard's "zero-gravity human-waste disposal system" by calling it a "space toilet" even though this creation proved to be useful, granted some minor issues that were eventually resolved. Despite not being a physicist and being subjected to Sheldon's endless insults, among his genius friends, Howard was the only person who went to space; he visited the International Space Station as a Payload Specialist on Expedition 31. By the time Howard came back home, Sheldon, who was secretly envious of the experience, also made the same comparison he made in Young Sheldon, saying that, like Howard, monkeys also went to space.

Over the years, however, Sheldon and Howard eventually found ways to genuinely get along with each other. While Sheldon continued to have tendencies to look down on him, it wasn't as bad as it was before. Howard, for his part, learned to block out his insults, much like Penny did when Sheldon mercilessly mocked his career, intellect, and even personal relationships. What's interesting is, if CBS wants another The Big Bang Theory spinoff like Young Sheldon, they might want to do a prequel off-shoot with Howard given his equally fascinating childhood.

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