6. But because words alone are not a sufficient declaration of the mind, as hath been shown chapter XIII. section 8, words spoken _de futuro_, when the will of him that speaketh them may be gathered by other signs, may be taken very often as if they were meant _de præsenti_: for when it appeareth, that he that giveth, would have his words so understood by him to whom he giveth, as if he did actually transfer his right, then he must needs be understood to will all that is necessary to the same. [Sidenote: Free gift defined.] 7. When a man transferreth any right of his to another, without consideration of reciprocal benefit, past, present, or to come, this is called _free gift_. And in free gift, no other words can be binding, but those which are _de præsenti_, or _de præterito_: for being _de futuro_ only, they transfer nothing, nor can they be understood, as if they proceeded from the will of the giver; because being a free gift, it carrieth with it no obligation greater than that which is enforced by the words. For he that promiseth to give, without any other consideration but his own affection, so long as he hath not given, deliberateth still, according as the causes of his affections continue, or diminish; and he that deliberateth, hath not yet willed, because the will is the last act of his deliberation. He that promiseth therefore, is not thereby a _donor_, but _doson_; which name was given to that Antiochus, that promised often, but seldom gave. [Sidenote: Contract, and the sorts of it.] 8. When a man transferreth his right upon consideration of reciprocal benefit, this is not free gift, but mutual _donation_, and is called _contract_. And in all contracts, either both parties presently perform, and put each other into a certainty and assurance of enjoying what they contract for, as when men buy or sell, or barter; or one party performeth presently, and the other promiseth, as when one selleth upon trust; or else neither party performeth presently, but trust one another. And it is impossible there should be any kind of contract besides these three. For either both the contractors trust, or neither; or else one trusteth, and the other not. [Sidenote: Covenant defined.] 9. In all contracts where there is trust, the promise of him that is trusted, is called a _covenant_. And this, though it be a promise, and of the time to come, yet it doth transfer the right, when that time cometh, no less than an actual donation. For it is a manifest sign, that he which did perform, understood it was the will of him that was trusted, to perform also. Promises therefore, upon consideration of reciprocal benefit, are covenants and signs of the will, or last act of deliberation, whereby the liberty of performing, or not performing, is taken away, and consequently are obligatory. For where liberty ceaseth, there beginneth obligation. [Sidenote: Contract of mutual trust, is of no validity in the estate of hostility.]