This represents an extreme case of "doubting folly" a case in which the victim could no longer concentrate his thoughts on the simplest proposition outside the narrow circle to which his doubts had restricted him.

If we once allow ourselves to wonder whether we have turned off the water, enclosed the check, or mailed the letter, it is but a step to an uncomfortable frame of mind which can be relieved only by investigating the matter. This compulsion once acceded to, it becomes more and more easy to succumb. The next step is to blur, by constant repetition, the mental image of the act. In extreme cases the doubter, after turning the gas on and off a dozen times, is finally in doubt whether he can trust his own senses. A certain officer in a bank never succeeded in reaching home after closing hours without returning to try the door of the bank. Upon finding it locked, he would unlock it and disappear within, to open the vault, inspect the securities, and lock them up again. I once saw a victim of this form of doubt spend at least ten minutes in writing a check, and ten minutes more inspecting it, and, after all, he had spelled his own name wrong!

Constant supervision only impairs acts which should have become automatic. We have all heard of the centipede who could no longer proceed upon his journey when it occurred to him to question which foot he should next advance.

To other doubts are often added the doubt of one's own mental balance; but it is a long step from these faulty habits of mind to real mental unbalance, which involves an inability to plan and carry out a line of conduct consistent with one's station.

It took a young man at least fifteen minutes, in my presence, to button his waistcoat. He felt the lower button to reassure himself, then proceeded to the next. He then returned to the lower one, either distrusting his previous observation, or fearing it had become unbuttoned. He then held the lower two with one hand while he buttoned the third with the other. When this point was reached he called his sight to the aid of his feeling, and glued his eyes to the lower while he buttoned the upper, unbuttoning many meantime, to assure himself that he had buttoned them. This young man said he would sometimes stop on his way to the store in doubt whether he was on the right street, a doubt not quieted either by reading the sign or by asking a stranger, because the doubt would obtrude itself whether he could trust his sight and his hearing, indeed, whether he was really there or dreaming. Even this victim of extreme doubting folly conducted his business successfully so long as I knew him, and so comported himself in general as to attract no further comment than that he was "fussy."

These doubts lead to chronic indecision. How often, in deciding which of two tasks to take up, we waste the time which would have sufficed for the accomplishment of one, if not both.

The doubt and the indecision result directly from over-conscientiousness. It is because of an undue anxiety to do the right thing, even in trivial matters, that the doubter ponders indefinitely over the proper sequence of two equally important (or unimportant) tasks. In the majority of instances it is the right thing for him to pounce upon either. If he pounces upon the wrong one, and completes it without misgiving, he has at least accomplished something in the way of mental training. The chances are, moreover, that the harm done by doing the wrong thing first was not to be compared to the harm of giving way to his doubt, and either drifting into a state of ineffective revery or fretting himself into a frenzy of anxious uncertainty.

A gentleman once told me that after mailing a letter he would often linger about the box until the postman arrived, and ask permission to inspect his letter, ostensibly to see if he had put on the stamp, but in fact to reassure himself that he had really mailed the missive, although he knew perfectly well that he had done so. The life of the chronic doubter is full of these small deceits, though in most matters such persons are exceptionally conscientious.

This form of over-solicitude is peculiarly liable to attack those in whose hands are important affairs affecting the finances, the lives, or the health of others. I have known more than one case of the abandonment of a chosen occupation on account of the constant anxiety entailed by doubts of this nature. Nor are these doubts limited to the question whether one has done or left undone some particular act. An equally insistent doubt is that regarding one's general fitness for the undertaking. The doubter may spend upon this question more time than it would take to acquire the needed facility and experience.

Some one has said there are two things that no one should worry about: first, the thing that can't be helped; second, the thing that can. This is peculiarly true of the former.