Back in 2012, Sam Simon — best known as one of the creators of The Simpsons — was told he had terminal colon cancer and only three to six months to live. Since then, he’s been preparing to give away his entire fortune to the causes that matter most to him.

In a recent interview with NBC News, Simon explained that most of these causes directly involve animals. He as worked closely, for example, with PETA founder Ingrid Newkirk.

“I think that my passion for the animals and against animal abuse is based on the knowledge that these creatures who feel and think can’t speak for themselves and they’re dependent on us for that,” he told interviewer Maria Shriver. “And so I feel it’s my responsibility to speak for those that can’t speak for themselves.”

The 59-year-old has put most of his money into the Sam Simon Foundation, which also works to feed families in need and provide service dogs for veterans.

Though Simon has struggled personally during his terminal diagnosis, he explains to Shriver that this is the happiest he’s ever been.

“Somehow, I ended up surrounded by people that love me and take care of me and will do anything for me,” he said. “It’s a good feeling. That’s called happiness.”

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