Exponential growth: fold a paper to the moon

One sheet of paper, a tenth of a millimetre thick. Fold it in half and you have two layers. Fold it again, four. Again, eight. Then sixteen. Doubling feels boring, and that is the trap. It is not boring. Seven folds and you are holding a notebook. Ten folds and it is as thick as your hand. Seventeen folds, and the stack is the height of a house. Twenty folds is a stadium. Twenty-seven folds is a city, thirteen kilometres of paper. And at thirty folds, the stack has left the atmosphere entirely. And at forty-two folds, the stack sails past the moon. Three hundred and eighty-four thousand kilometres away. Four point four trillion layers of paper. There is no trick hiding in this. No magic. It is one sheet of paper, and the words times two, said forty-two times. The same curve runs compound interest, one infection becoming a pandemic, and an algorithm that quietly kills your server. Your gut has no instinct for doubling. Nature never trained you for it, and that blind spot is where fortunes and disasters both hide. Linear adds. Exponential multiplies. That is the entire gap, and almost nobody feels it until it has already happened to them.