In the attempt to make scientific discoveries, every problem is an opportunity — and the more difficult the problem, the greater will be the importance of its solution.

Source: "Advice to Young Scientists." TEDMED 2012. Apr. 2012. Conference Presentation. Additional Information: This quote is from biologist E.O. Wilson's 2012 TED Talk, which gives advice to young scientists. The quote means that as scientists work to solve difficult problems, the innovations resulting from this work will become more and more momentous. Watch the full TED Talk here: E.O. Wilson - Advice to Young Scientists