I once did speculate about this very possibility, back in the '70s and came up with a paradoxical scenario: Suppose by prearrangement -- or just by luck (?) -- two oppositely time-oriented humanoids met in the same room in some habitable place for one hour -- A of them arriving at noon, planning to stay until 1 p.m., and B arriving at 1 p.m., planning to stay until noon (in some fixed time zone calibration). They sit quietly in separate chair for 1/2 hour "after" their arrivals, where this refers to noon to 12:30 for A, but refers to 1 p.m. to 12:30 for B. Unfortunately, B runs amok at 12:30 p.m., whips out his pistol and shoots A, resulting in what would normally be an immediately fatal injury to A. --Dan << I will not attempt to speculate about what one might observe if a visitor from a faraway part of the universe arrived here with time reversed orientation. _____________________________________________________________________ "It don't mean a thing if it ain't got that certain je ne sais quoi." --Peter Schickele