Abstract
“Fiiirre!” If someone were to shout that while you were in the midst of reading this essay, you would, like most people, stop reading and look around the room for the source of the shout, or the fire itself. You would also consider whether the likelihood of a fire was sufficiently high to cause you to take appropriate action – for example, locate a fire extinguisher, call the fire department, or leave the room. Of course, you have not been sitting around waiting for someone to yell “Fire!” You were engaged in some task (unrelated to fires), yet were able to react to that stimulus. By contrast, if you were a police officer who was being trained at a firing range, you would be doing exactly that (i.e., waiting for someone to yell “Fire!”), and when you heard “Fire,” you would pull the trigger on your weapon, rather than look around for the source of the cry.