"It really changes your perspective on the world," Pitt, 42, said during a Today show interview aired Monday morning. "You know, I've had my day. I made some films, and I've really had a very fortunate life, and it's time for me to share that a little bit."
Admitting that he shares his partner Angelina Jolie's belief in contributing to humanitarian causes, Pitt also credited the couple's kids – Maddox, 4, Zahara, 1, and 6-week-old daughter Shiloh – with the shift in his attitude.
Having children, he said, "completely changes your perspective and certainly takes the focus off yourself, which I'm really grateful for." Chuckling, he added: "I'm so tired of thinking about myself. I'm sick of myself."
Of parenting, he said, "You feel you want to be there and not miss out on anything. It's a true joy (and) a very profound love. You can write a book, you can make a movie, you can paint a painting, but having kids is the most extraordinary thing I've ever taken on."
And of Shiloh, he revealed, "Man, if I can get a burp out of that little thing I feel such a sense of accomplishment."
Pitt's interview took place during his weekend visit to New Orleans, where he met with community leaders to lend his support to a Global Green effort for affordable, eco-friendly housing.
"It's shocking," Pitt said of the lack of progress in the hurricane-ravaged area. "Driving by houses in the Ninth Ward ... it is just devastating."