“…If such voluntary rewards were enforceable, it would create a 'preference of voluntary undertakings to claims for just debts […], and voluntary undertakings would also be multiplied, to the prejudice of real creditors'. 57 In English law, past consideration is only acceptable, as an exception, if it was provided at the promisor's request, and if the parties intended the performance to be rewarded at the time when it was undertaken and that the reward must have been legally recoverable. 58 In substance, German law is very much in line with English law in this regard, but it has not yet acknowledged this, nor has it acknowledged the benefit of drawing by comparison on the ideas underlying the doctrine of consideration.…”