If physics needs an interpretation, in rather the way a formal language does, if it is to be meaningful, doesn’t that show that metaphysics is indispensable? Physical knowledge can’t be all the knowledge there is, because the formulas of physics stand in need of interpretation. Are electrons continuant particulars or are they just sequences of events? Are there categorical properties lurking behind the dispositions to motion we observe? Are particles really nothing but fields? Is consciousness present even at the most fundamental level? Physics itself doesn’t answer these questions, so that complete knowledge of the physical world requires metaphysical knowledge in addition to physical knowledge in the strict sense. You can’t know the nature of the physical world by knowing physics alone.