"You don't? Well, perhaps you need some help. For instance, Mr. Reed, can you give me an estimate of the useful land area of Eden, Tau Ceti?"
"Sir, the total land area is about fifty million square miles. Perhaps about half of that is useful, or could be."
"Ah. You said 'could be'. Why, Mr. Reed?"
"Let's put it this way, sir. Whether a given acreage is useful often depends upon how badly it is needed. For instance, a plot of wooded land might well be ignored for centuries by a sparsely populated agrarian culture who had a lot of open plain to cultivate. At a later date, an increasing pressure of population might make it expedient and sensible to clear vast areas of tree stumps, boulders and all sorts of hazards."
"And here on Eden?"
"Well, sir, at the present time the population of Eden is about a hundred thousand. Fertile plains are growing wild with weeds because the land isn't needed yet. That is—er—"
"That is what?"
"Maybe I shouldn't have said 'wild with weeds' sir. After all, they have been encouraged. I'm told that the atmosphere smelled a lot stronger when Man first arrived."
The commander sniffed and said, "It's pretty strong right now."