A novel theory of comparative risk is developed and defended. Extant theories are criticized for failing the tests of extensional and formal adequacy. A unified diagnosis is proposed: extant theories consider risk to be a univariable function, but risk is a multivariate function. According to the theory proposed, which we call the unified theory of risk, the riskiness of a proposition is a function of both the proportion and the modal closeness of the possible worlds at which the proposition holds. It is argued the theory passes the tests of extensional and formal adequacy.

中文翻译：

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统一的风险理论


一种新的比较风险理论被开发并捍卫。现存的理论因未能通过外延和形式充分性的测试而受到批评。提出了一个统一的诊断：现存的理论认为风险是一个单变量函数，但风险是一个多变量函数。根据所提出的理论，我们称之为统一风险理论，一个命题的风险性是该命题所处的可能世界的比例和模态接近性的函数。有人认为该理论通过了扩展和形式充分性的测试。