AbstractAccording to common conception, laws should make actors internalize all the costs and benefits of their actions to make them behave efficiently. This article shows that even when only partial internalization is possible, private law can create efficient incentives by ensuring that each actor internalizes an identical proportion of the costs and benefits.This proportional internalization principle has profound implications. In tort law, it offers a new mechanism for dividing liability between multiple parties. In contract law, it suggests a new default rule for joint ventures. And, in restitution law, it presents an alternative doctrinal formulation for restitution for unrequested benefit.

中文翻译：

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私法中的比例内化原则

摘要按照普遍的观念，法律应该使行为者内化其行为的所有成本和收益，以使其行为有效。本文表明，即使只有部分内化是可能的，私法也可以通过确保每个行为者内化相同比例的成本和收益来创造有效的激励措施。这种比例内化原则具有深远的意义。在侵权法中，它提供了一种在多方之间划分责任的新机制。在合同法中，它为合资企业提出了一项新的默认规则。并且，在归还法中，它提出了一种替代的教义表述，用于归还未经请求的利益。