This article revisits the case in which the Hand formula was born and examines whether Judge Hand’s ruling in that case For a more detailed explanation, you can watch a video the explains the Learned Hand formula in more detail. Abstract. (1947) is canonized in the law-and-economics literatu re as the first use of cost-benefit analysis for determining negligence and assigning liability. Learned Hand Formula: Learned hand formula is an important process to assess negligence or fault. The Formula is P x L > B Where P view the full answer If PL exceeds B, then the defendant should be liable. Learned Hand used the following algebraic formula to explain breach of duty: B