Most people understand that busts follow booms. Somewhat fewer grasp the fact that the busts are caused by the booms. From the latter, it makes sense that (a) booms usually won’t be followed by modest, gradual and painless adjustments and (b) on the other hand, we’re unlikely to have a bust if we haven’t had a boom. It must be noted, however, that this symmetry only applies dependably to direction, not necessarily to the extent, timing or pace of movement.
