Originally Posted by
Xaqaria
Because I don't like anyone invoking occam's razor since nobody seems to get it, lets clarify. The statement "A meteorite was found with bacteria fossils in it" has two assumptions, that a meteorite was found and that there was bacteria fossils in it. The statement "a meteorite was found with bacteria fossils in it and the bacteria is extraterrestrial in origin." has 3 assumptions (was found, has bacteria fossils, from space), and is less likely to be true. The statement "a meteorite was found with bacteria fossils in it and the bacteria is terrestrial in origin." has 3 assumptions and is less likely to be true (than the first statement). Neither of these assumptions (space, earth) is more or less likely than the other, even if one is more "plausible".