Part Payment Problem

The question here is 'What has D given in consideration to support D's claim for being absolved from paying the remaining £100?' C clearly has given up the right to receive that £100 but was has D given in exchange. And, according to your (brief) scenario, it seems that D has given nothing So we're now looking at a one-sided contract, a specialty contract where consideration is flowing only one way. And if this specialty contract is to be enforceable, then it should be under seal (signed, sealed and delivered in the presence of witnesses) There's no mention of sealing in your scenario so I suggest that D cannot rely on the contract and that C will be able to pursue D for the remaining £100 If D had said "Will you accept £900 and an empty bird cage in full and final settlement?" then the payment of £900 together with the handing over of an empty bird cage would have absolved D from further payment Isn't law wonderful!

Sorry, I forgot about Pinnel According to the internet (https://en.wikipedia.org/wiki/Pinnel%27s_Case) the main 6 (six) exceptions to Pinnel are : The exceptions to the rule in Pinnel’s case include: Payment accompanied by fresh consideration; Prepayment of debt at the creditor’s request; Payment of a lesser sum at another place at the creditors request; A contract with creditors after insolvency of the debtor; The parties enter into a deed of release; and Promissory Estoppel. Now, just reading those 6 exceptions, it strikes me that there isn't a whole lot that needs explanation. They all seem to me to be self-explanatory. BUT, importantly, do you agree? If not post again OK?