In Western films, the gunslinger that draws first always gets shot. This seems like a standard Hollywood trope but it diverted the attention of no less a scientist that Niels Bohr, one of history’s greatest physicists. Taking time off from solving the structure of the atom, Bohr suggested that it takes more time to initiate a movement than to react to the same movement. Perversely, the second gunslinger wins because they’re responding to their opponent’s draw.

Now, Andrew Welchman from the University of Birmingham has found that there’s something to Bohr’s explanation. People do indeed have a “reactive advantage”, where they execute a movement about 10% more quickly if they’re reacting to an opponent. Of course, ethics committees might