The butterfly effect

What is the future?? If all depends on our choice of the moment and there is no fixed outcome and every action can have a million results and it is influenced so many things then what is it that pushes people to have to make what the society considers the perfect choices. Can the flapping of a butterfly in one place cause a tornado at another?? If it does then what is the significance of numbers and theories or mathematics that spends all it's considerable history telling us everything has a fixed result. Which is right mathematics or the science behind the butterfly effect? And if the math is right then how can it be so hard to predict the future?