It's amazing how much information swims around in the minds of human beings. Yet, how often do we access our full range of knowledge, let alone apply it? Our world is one of instant gratification and automated answers. In their everyday lives people are given less and less motivation to thoroughly think things through.
Modern conveniences are replacing our mental processes. For example, cashiers no longer need to know how to tabulate the amount of change customers' get back following a purchase. A machine does that for them instantly.