sitting can you just fly off you say no right now from where you're sitting can you get up and walk you'll say yes what is the basis of this why you say no to flying and yes to walking because past experience of life many times you've gotten up and walked never did you fly off or in other words you're using the past experience of life as a basis for deciding whether something is possible or not possible or in other words you have decided that what has not happened till now cannot happen in your life in future