Two astronauts land on Mars. Their mission: to check whether there
is oxygen on the planet. "Give me the box of matches" says one.
"Either it burns and there is oxygen, or nothing happens." He
takes the box, and is ready to strike a match when, out of the
pink, a Martian appears waving all his arms..."No, no, don't!"
The two guys look at each other, worried. Could there be an
unknown explosive gas on Mars? But he takes another match...
By now, a crowd of hysterical Martians has gathered around them,
all waving their arms: "No, no, don't do that!"
"It looks serious. What are they afraid of?" says the first
atronaut. "Forget it," says the other, "we're here for science -
to know if man can breathe on Mars." He strikes a match, which
flames up, burns down, and ... nothing happens.
"Why did you try to stop us striking the match?" asks the
astronaut.