In our mind there is so many thoughts comes daily which comes without any conclusion or without any practical usage. every information or thought it gets, calculates and reaches a conclusion.
And when it comes to the fact of mind not being a vessel to be filled, but a fire to be kindled, undoubtedly it's cent per cent true. When we give a little more thought to the saying, its amazing how very deep a meaning it offers.
Consider this single instance- suppose Galilio didn't kindle his curiosity, suppose he filled his head with the wrong ideas. I don't need to tell you any further.