12 BUSINESS OF LIFE INSURANCE

is feasible, though usually not desirable, when it is applied only at the ages of youth and of middle life, but a change must be made to level premiums before old age comes on; for, with the rapid convergence of the mere risk into a certainty of death, no other form of insurance is practicable, except level premium insurance.

Yet all forms of level premium, whole life insurance, whether with premiums for life or for a term of years only, are precisely the mathematical equivalents of increasing premiums, and, if all men were clear-headed and fully informed, so that a man would carry his insurance so long as he wants it and no longer, and if at the higher ages men would not drop it rather than pay its average cost, when they consider their chances better than the average, it would be just as economical for a man to carry his insurance on the increasing premium plan, taking into account his payments and his indemnity. as upon any other plan.

To arrive at the method of computing a level premium, let us first consider how we would go to work to calculate the single premium. Let us assume the following mortality table to rep-resent the experience to be expected :