FIRST INGREDIENT, GENEROSITY
This is a subtle element and merges into a sense of obligation on slight provocation. You feel that your position in life is more fortunate, and pity enters your thought. If an extra service is given, in reality or in appearance, the servitor has pitched his appeal upon the ground of obligation. Few persons can rest easily until a sense of obligation is discharged through some form of compensation. The opportunity to balance the account comes when cash is being passed between you and the person serving. You offer a cash consideration proportioned to your sense of obligation.
Inasmuch as the whole argument in favor of tipping is based upon the allegation that the servitor actually gives a value in extra service, the element of obligation will be examined closely.
The Pullman porter or the waiter who can succeed in making a patron feel a sense of obligation knows that he has assured a tip for himself. The company or the restaurant business is a vague fact, while the man hovering over your berth or table is a most tangible relation. His art is to make the patron feel that he is responsible for the careful attentions. In a subconscious way the patron knows that the price of the ticket or the food includes the service (wages of the porter or waiter) but the obsequious alertness of the attendant overshadows this knowledge. It is present personality versus an abstract entity known as company or restaurant. Hence, though the price of the ticket or the payment of the check pays for the porter's or waiter's service, the patron has been made to feel a second obligation which he discharges with a tip.