I think it's imperative to follow your heart and choose a profession you're passionate about, and if you haven't found that 'spark' yet, if you're not sure what you want to do with your lives - be persistent until you do.
“Millions of men have lived to fight, build palaces and boundaries, shape destinies and societies; but the compelling force of all times has been the force of originality and creation profoundly affecting the roots of human spirit.”