In The Empire Strikes Back, Yoda is training Luke to lift his sunken X Wing fighter with his Jedi powers. Luke thinks it’s impossible, but he says he’ll try. Yoda chastises him, saying “Do or Do not, there is no try”.

Star Wars creator George Lucas said in an interview, “The philosophy of ‘put your all into something, and don’t just try’, but actually envision yourself doing it and accomplishing it, is a philosophy that runs through all my movies. It is something that I encountered first when I was in college, a lot of the students would give up on things before they really had a chance to explore them, they would convince themselves that it was not possible. For me, it was the whole issue of getting to make movies, was a completely impossible idea, there was no even remote consideration that it could actually happen. But, I put my mind to it, and never considered any other possibility. It was through that, that eventually I did manage to do the impossible. It’s only by considering the impossible, that one can get to it. You can’t get to it by simply saying, “I’m going to try to get to it”, you have to say “I’m GOING to get to it.”

I want to emphasize the important points. George Lucas saw that lot of people give up on things before they really have a chance to explore them. A lot of times they’ll convince themselves it is impossible. Before George Lucas became successful, making movies also seemed impossible, but he put his mind to it, and didn’t consider any other possibility. He believed it was possible even before he was able to do it. That’s how he was able to become a film director and make Star Wars.

After Luke gives up, Yoda raises the X Wing Fighter himself with the Force, and Luke, astonished, exclaims “I don’t believe it”. Yoda, tired from his effort, says “That is why you fail”.