"No one tests the depth of a river with both feet" (Ashanti Proverb).
PRUDENCE MEANS BEING CAREFUL. It means using wisdom, good judgment, and common sense in deciding one's course of action. When the harmful consequences of a plan's failure would be greater than the helpful consequences of the plan's success, prudence will say, "Don't do it." In the game of Russian roulette, for example, a person has a five-out-of-six chance of winning. But that sixth chance is so dire that a prudent person would not play the game at all. It's prudence that keeps us from "courting disaster," as the saying goes.
Some other less-than-desirable traits often masquerade as prudence, of course. "Prudence is no doubt a valuable quality," wrote Robert Cecil, "but prudence which degenerates into timidity is very seldom the path to safety." So whenever we say we're being prudent, it's often worth asking whether we're being that or just plain timid.
And not only that, there are many times when prudence should not be the governing factor. From the standpoint of common sense, doing the right thing is often very imprudent, and many of the noblest deeds in the history of the world would never have been done had their doers allowed prudence to decide the question. Robert Hall summed it up nicely in this way: "In matters of conscience, first thoughts are best; in matters of prudence, last thoughts are best."
But properly understood and wisely exercised, prudence is a very good thing indeed. It would be a coward who never considered anything but the counsels of prudence, but it would be a fool who never consulted prudence at all. Prudence should always be given a seat at the table when significant matters are being decided.
In the end, I think the best way to look at prudence is to see it as something that helps us in the areas of restraint and reserve. In this age of uninhibited excess, we need to get reacquainted with some things like simplicity and understatement. It may be trite, but it's also true: less is sometimes more. Prudence can help us to get that "more" by putting the brakes on our runaway trains of thought.
"Tell not all you know, believe not all you hear, do not all you are able" (Italian Proverb).