ten days of the working year to make a new plane. If William had not borrowed the plane he would have taken ten days to make himself a plane, which he could have used for the remaining 290 days. Thus, if we take a plank to represent the fruits of a day's labor with the aid of a plane, at the end of the year, had no borrowing taken place, each would have stood with reference to the plane as he commenced, James with a plane, and William with none, and each would have had as the result of the year's work 290 planks. If the condition of the borrowing had been what William first proposed, the return of a new plane, the same relative situation would have been secured. William would have worked for 290 days, and taken the last ten days to make the new plane to return to James. James would have taken the first ten days of the year to make another plane which would have lasted for 290 days, when he would have received a new plane from William. Thus, the simple return of the plane would have put each in the same position at the end of the year as if no borrowing had taken place. James would have lost nothing to the gain of William, and William would have gained nothing to the loss of James. Each would have had the return his labor would otherwise have yielded—viz., 290 planks, and James would have had the advantage with which he started, a new plane.
But when, in addition to the return of a plane, a plank is given, James at the end of the year will be in a better position than if there had been no borrowing, and William in a worse. James will have 291 planks and a new plane, and William 289 planks and no plane. If William now borrows the plank as well as the plane on the same terms as before, he will at the end of the year have to return to James a plane, two planks and a fraction of a plank; and if this difference be again borrowed, and 10 on, is it not evident that the income of the one will
