really gotta wonder if he really said it or its misattributed to him.
At least he said that. Not sure if he was first to say that though.
Apparently when his martial arts teacher told him he was too forceful, to be more like water, and then banned him from practicing until he understood. Short story, he went on a boat ride, got angry, started punching the river, then he got that aha moment.
Bruce Lee was actually a really wise dude. I also highly recommend the podcast.