The Weather and the Words in Passing : Page 238

All these comments are really informal reference reports. By means of them much of the work and play of the world is carried on. But just as in letters of reference and recommendation, so these informal comments ought to be scrupulously honest. And they should be rendered only with caution to the right persons and for the right purpose. But certainly they cannot be prohibited. They are necessary. The important thing about them is that they must be kept confidential. A comment of reference, whether formal or informal, carries with it the absolute obligation not to relay it, not to dishonor it by publication. Next to recognized villains, one can hardly imagine more vile and insidious characters than these who violate such informal confidences.