We have to beef up our searches, which are now pretty dismal, so we can find out about these things before we get hit. … It takes a dramatic event to get people's attention, and we thought the comet crash with Jupiter might have done the job. … we tend to ignore an extraterrestrial hazard that could reduce the planet to rubble. … What we really need is a good scare.
Comets cannot be homes of life; they are not sufficiently condensed; indeed, they are probably but loose congeries of small stones. But even if comets were of planetary size it is clear that life could not be supported on them; water could not remain in the liquid state on a world that rushed from one such extreme of temperature to another.
Moreover, I desire that with the plan of the wise rulers and with their authority, pious and learned men at some time be called together both from our own churches and the churches of other nations in order that there might be a deliberation about all these controversies, and that one consenting form of doctrine, true and clear and without any ambiguity, might be handed down to posterity.