I think that's spot on. When people say something is a first/ second/nth, order effect they are really just arbitrarily drawing discrete lines in a continuous c

I think that's spot on. When people say something is a first/ second/nth, order effect they are really just arbitrarily drawing discrete lines in a continuous chain of causality. The problem of where to draw those lines is so difficult that legal systems resort to constructing tests based on whether a "reasonable person" could have foreseen the specific consequence of an act.