To the editor: In 1960, an astronomer proposed a mathematical model

Explanation

The conclusion that we’re directed to make Clay “reconsider” is signaled by the phrase “This indicates that...,” and the gist of it is that it’s a rebuttal: For Clay, life as we know it exists nowhere but on Earth, despite the astronomer’s prediction that lots of life is to be found on planets Out There.

Notice that Clay spends most of his letter describing the astronomer’s thought process. He provides only one piece of counter evidence, and it’s this: No single planet outside of our own solar system has been found. On that absence of evidence hangs Clay’s stubborn, categorical insistence that We Are Alone. Well, he’d have to back off if, as (C) states, the reason that no other planets have been found is not that they don’t exist, but that we don’t yet have the means to find them. If (C) is true, then until such time as adequate means of detection is developed, the astronomer’s prediction is unscathed and will have to stand.

(A) sounds like a capitulation on Clay’s part, but it’s really outside the scope. The point at issue between Clay and the astronomer is whether life as we know it exists elsewhere than Earth. Clay could concede the existence of (A)’s weird life forms and still argue that the astronomer is wrong.

(B) Planets and a star like the Sun are, to the astronomer, necessary for life as we know it to exist. That some stars may be planet-less has no effect on either the astronomer’s logic or Clay’s.

(D) is something that Clay already accepts as true—his whole rebuttal hinges on his belief that it’s the astronomer’s faulty assumption (about other planets) that renders the prediction worthless. Since (D) is in synch with Clay’s reasoning, it cannot serve to make him reconsider that reasoning.

(E) is irrelevant. So communication between us and E.T. would be tough, eh. Would it be impossible? What has this to do with whether life as we know it does or does not exist?

Answer: C