David Heinemeier Hansson of 37signals and the creator of Ruby on Rails delivers a powerful lecture at Standford University’s Entrepreneurship Program.

He says that planning is guessing, and for a start-up, the focus must be on today and not on tomorrow. He argues that constraints–fiscal, temporal, or otherwise–drive innovation and effective problem-solving. The most important thing, Hansson believes, is to make a dent in the universe with your company