![Robert Cordova](http://phibetaiota.net/wp-content/uploads/2015/07/robert-cordova.jpg)
Arrationality is an evolving term. It evolves specifically in reaction to rationality. Arrationality is as much a part of the 500-year process of welcoming science into our consciousness as anything else. In this sense, arrationality was how people thought before the early modern era began around 1500 – admittedly not always to the greatest effect.