Now the astute negotiator will not likely believe everything he hears, nor accept advice which he cannot test; he must examine the origin of information, as well as the interest and the motives of those who offer it him. He must attempt to discover the means by which they themselves have acquired it, and he must compare it with other information to see whether it tallies with that part which he knows to be true. There are many signs by which a discerning and penetrating mind will be able to read the truth by placing each link of information in contact with another. For this purpose no rules can be drawn up for the guidance of a diplomat in such a matter, for unless a man be born with such qualities he cannot acquire them, and to those who do not possess them I might as well speak to the deaf as write these observations. [Sidenote: _The Flair for Secrets._] A negotiator can discover national secrets by frequenting the company of those in authority, and there is not a court in the world where ministers or others are not open to various kinds of approach, either because they are indiscreet and often say more than they should, or because they are discontented and ready to reveal secrets in order to satisfy their jealousy. And even the most practised and reliable ministers are not always on their guard. I have seen highly trained and well-proven statesmen who none the less in the course of conversation, and by other signs, allowed expressions to escape them which gave important clues to their policy. And there are courtiers at every court who, though not members of the King’s Council, know by long practice how to discover a secret, and who are always prepared to reveal it in order to show their own importance and their penetration. It is almost impossible to conceal from an active, observant, and enlightened negotiator any important design of public policy, for no departure of state can ever be made without great preparation which entails the sharing of many secrets by many persons, and this is a danger against which it is almost impossible to guard even by those who take the greatest precautions. [Sidenote: _On the Transmission of Information._]