There may be two kinds of alienation, the one of our property, the other of a certain portion of our liberty. Under those of the former kind we may class the promises of gifts, and under the latter the promises of doing certain actions. On this subject we are supplied with noble arguments from the divine oracles, which inform us, that God himself, who can be limited by no established rules of law, would act contrary to his own nature, if he did not perform his promises. From whence it follows that the obligations to perform promises spring from the nature of that unchangeable justice, which is an attribute of God, and common to all who bear his image, in the use of reason. To the proofs of scripture here referred to, we may add the judgment of Solomon, "My son if thou hast been surety for thy friend, thou hast tied up thy hands to a stranger; thou art ensnared by the words of thy mouth, then art thou taken by the words of thine own mouth." Hence a promise is called by the Hebrews a bond or chain, and is compared to a vow. Eustathius in his notes on the second book of the Iliad, assigns a similar origin to the word ὑποσχεσεως {hyposcheseôs} or engagement. For he who has received the promise, in some measure takes and holds the person, that has made the engagement. A meaning not ill expressed by Ovid in the second book of his Metamorphoses, where the promiser says to him, to whom he had promised, "My word has become yours." After knowing this, there remains no difficulty in replying to the arguments of Connanus. For the expressions of the lawyers, respecting BARE PROMISES, refer only to what was introduced by the Roman laws, which have made a FORMAL STIPULATION the undoubted sign of a deliberate mind. Nor can it be denied that there were similar laws among other nations. For Seneca, speaking of human laws, and promises made without proper solemnities, says, "What law, _of any country, we may add_, obliges us to the performance of bare promises?" But there may naturally be other signs of a deliberate mind, besides a formal stipulation, or any other similar act which the civil law requires, to afford grounds for a legal remedy. But what is not done with a deliberate mind, we are inclined to believe does not come under the class of perfect obligations; as Theophrastus has observed in his book on laws. Nay, even what is done with a deliberate mind, but not with an intention of conceding our own right to another; though it cannot give any one a natural right of exacting its fulfilment, yet it creates an obligation not only in point of duty, but in point of moral necessity. The next matter to be considered is, what are the requisites to constitute a perfect promise.