Another exception is that the partial debt by a third party, in return for a promise of relief of the entire amount, prevents the creditor from subsequently suing the debtor for full payment (see Welby v Drake). In any event, if the promisor provides what he was obliged to do under public law, the promised fulfilment of the existing obligation is in any event not a good consideration. At Collins vs. Godefrey, Godefrey promised to pay Collins for his testimony. It was found that Collins failed to keep his promise, as he was in any event subject to a legal obligation to testify.  Similarly, if a party already has a legal obligation to do something, this cannot be a new consideration either. The reason why both exist in common law jurisdictions is considered by leading scholars to be the result of the combination of two different sons by the judge of the 19. First, the requirement of consideration was central to the action of Assumpsit, which had grown up in the Middle Ages, and until 1884, when the old forms of action were abolished, the normal complaint of breach of a simple contract remained in England and Wales; Second, the notion of agreement between two or more parties was promoted as the essential legal and moral basis of the treaty in all legal systems by the eighteenth-century French writer Pothier in his treatise on obligations, which was widely read by English judges and jurists (especially after the English translation in 1805). The latter fit well with the fashionable theories of will of the time, particularly John Stuart Mill`s influential ideas on free will, and was stacked on the traditional common law requirement for consideration to base an action in the assumpsit.  Let`s look at the uncle`s situation at the top.
If the same uncle had instead made the following offer to his 13-year-old nephew: „If you don`t smoke cigarettes, don`t drink alcohol, swear or play cards for money (gambling), I`ll pay you $5,000.“ On the nephew`s 21st birthday, he asks the uncle to pay, and this time the nephew can win in the ensuing lawsuit.  Although the promise not to drink and gamble alcohol under the age of 21 was not a valuable reflection (it was already prohibited by law), most states allow smoking at the age of 18 and the curse, while some consider it vulgar, at no age is illegal. Although smoking is limited by law until the age of 18, it is legal for people over the age of 18 and, therefore, the promise to renounce it has full legal value. However, the uncle would still be exempted from liability if his nephew drank alcohol when that consideration had no value because it was associated with something of legal value; Therefore, compliance with the entire collective agreement is necessary. A promise is enforceable if it is supported by the counterparty, i.e. if the counterparty has distanced itself from the promise. For example, in the case of Tweddle vs. Atkinson, William Guy promised that he would pay a sum of money to William Guy`s child, and likewise William Guy promised John Tweddle that he would pay a sum of money to John Tweddle`s child if both children were married. . . .