"There, Mart, is one for the massive old bean to concentrate on," challenged Seaton: then, as Crane considered the question in silence for some time he went on: "I'll answer it myself, then, by asking another. Why not? Why shouldn't they be? Remember, man is the highest form of earthly life--at least, in our own opinion and as far as we know. In our wanderings, we have picked out planets quite similar to our own in point of atmosphere and temperature and, within narrow limits, of mass as well. It stands to reason that under such similarity of conditions, there would be a certain similarity of results. How about it, Mart? Reasonable?" "It seems plausible, in a way," conceded Crane, "but it probably is not universally true." "Sure not--couldn't be, hardly. No doubt we could find a lot of worlds inhabited by all kinds of intelligent things--freaks that we can't even begin to imagine now--but they probably would be occupying planets entirely different from ours in some essential feature of atmosphere, temperature, or mass." "But the Fenachrone world is entirely different," Dorothy argued, "and they're more or less human--they're bipeds, anyway, with recognizable features. I've been studying that record with you, you know, and their world has so much more mass than ours that their gravitation is simply frightful!" "That much difference is comparatively slight, not a real fundamental difference. I meant a hundred or so times either way--greater or less. And even their gravitation has modified their structure a lot--suppose it had been fifty times as great as it is? What would they have been like? Also, their atmosphere is very similar to ours in composition, and their temperature is bearable. It is my opinion that atmosphere and temperature have more to do with evolution than anything else, and that the mass of the planet runs a poor third." "You may be right," admitted Crane, "but it seems to me that you are arguing from insufficient premises." "Sure I am--almost no premises at all. I would be just about as well justified in deducing the structure of a range of mountains from a superficial study of three pebbles picked up in a creek near them. However, we can get an idea some time, when we have a lot of time." "How?" "Remember that planet we struck on the first trip, that had an atmosphere composed mostly of gaseous chlorin? In our ignorance we assumed that life there was impossible, and didn't stop. Well, it may be just as well that we didn't. If we go back there, protected as we are with our rays and stuff, it wouldn't surprise me a bit to find life there, and lots of it--and I've got a hunch that it'll be a form of life that'd make your grandfather's whiskers curl right up into a ball!" "You do get the weirdest ideas, Dick!" protested Dorothy. "I hope you aren't planning on exploring it, just to prove your point?"