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Still, the 45-year-old actor, who's played Dr. Sheldon Cooper since the CBS sitcom debuted in 2007, believes that after 12 seasons on the show, it's the "right time" for him to move on.
"I guess at a personal level, it feels like the right time in my life," Parsons told Entertainment Weekly. "I don’t know what’s next for me. It’s not like there is something specific I am aiming for. I’m firmly in my middle age now. I don’t know how much longer I can wear (the T-shirts) without looking really long in the tooth."
Beside, Parsons wondered, after so many seasons, how many more stories are there to tell about Sheldon and his science-loving pals?
"It felt like we have been able to do this for so many years now, it doesn’t feel like there is anything left on the table. Not that we couldn’t keep doing it, but it feels like we’ve chewed all the meat off this bone," said the actor.
All finales come with a mix of emotions, said the star, who's bracing himself for when the show's finale episode airs this spring.
"In a way, it’s exciting. What is this next chapter of life? What is this next chapter for all of us?" he asked. "It will be very, very sad when it does end, even knowing (I am) okay with it. People are okay when they graduate but there are frequently tears at graduation.
"It’s hard to say goodbye to people that you have worked with for so long," he added of his co-stars.
Last August, shortly after CBS revealed "The Big Bang Theory" would wrap, Parsons took to Instagram to salute his cast members.
"You are all my playmates that I have fallen in love with and who have become a part of my life on set and off," he wrote next to a behind-the-scenes cast photo.
"I will miss all of you and all of this more than I can say and more than I can know at this time," he added.