how sure are you????

now how sure are you that the earth is spherical....didn't we believe it was flat earlier on......how sure are you that the earth revolves around the sun in an orbit......didn't we believe that the sun revolved around earth earlier.......are you sure that you made the choice that puts where you are today.....are you sure live doing what you love.......are you sure you still love doing what your doing now.......how sure are you that your happy now......if not how sure are you that you'll find happiness......how sure are you of anything.....????? but.........isn't this what makes life soooooo much fun!!!!!!!!!!!