f(R) Gravity is the most natural extension of General Relativity within Riemannian Geometry. Due to (inter alia) its potential capacity for a unified treatment of early and late-time cosmic expansion, it has enjoyed recent attention in astrophysics and cosmology. I critically examine three inter-related claims found in the pertinent physics literature, of general interest to the philosopher of science. 1. f(R) Gravity is equivalent to a particular Brans-Dicke Theory. 2. The spacetime geometry underpinning f(R) Gravity has substantial conventional elements. 3. f(R) Gravity is an instance of a theory in which the distinction between matter and spacetime is conventional. Whilst the first claim can be vindicated in precise terms, the remaining two claims, I submit, are unwarranted – at least for the reasons usually adduced. On different grounds, though, the case for conventionalism about spacetime geometry in f(R) Gravity (as well as General Relativity) turns out to be considerably stronger.

f(R) 引力是广义相对论在黎曼几何中最自然的延伸。由于（除其他外）它具有统一处理早期和晚期宇宙膨胀的潜在能力，它最近在天体物理学和宇宙学中受到关注。我批判性地研究了科学哲学家普遍感兴趣的相关物理文献中的三个相互关联的主张。1. f(R) Gravity 等效于特定的 Brans-Dicke 理论。2. 支撑 f(R) Gravity 的时空几何具有大量的常规元素。3. f(R) Gravity 是一个理论的例子，其中物质和时空之间的区别是常规的。虽然第一个主张可以精确地证明是正确的，但其余两个主张，我认为，是没有根据的——至少出于通常引用的原因。基于不同的理由，