THE THEORY OF INTEREST

degrees of impatience pertaining to different income sit-uations. These directions, or divergences from the 45°line, picture to us how the individual would be willingto borrow or lend under all possible income circumstances.

§8. A Typical Family of Willingness Lines

While we cannot, of course, tell exactly how any humanbeing would act if far from the income situation in whichhe is actually placed, yet we know what in a way wouldbe characteristic of him. Chart 31 is believed to represent

CHART 31

A Typical Family of W Lines.

roughly a family of Willingness lines typical of mosthuman beings. It is best analyzed by following the dottedstraight line SS' running northeast, midway between theaxes and therefore comprising points which represent, ineach case, equal incomes in both years.

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