  Spinoza’s argument to IIIp6 is uncharacteristically insulated from the rest of the Ethics. As Spinoza presents the argument at IIIp6d, it depends principally upon IIIp4, a proposition which Spinoza takes to be self-evident, and IIIp5 which derives from IIIp4 alone. The argument also involves, less directly, IP25C and its gloss at IP34. 