 The first assumption that all perfectly natural properties are intrinsic has been rejected by Weatherson (2006). (See also Yablo 1999 who holds that, even if every perfectly natural property is intrinsic, this fact is at best a lucky accident, and that this renders Lewis’s account unsuccessful as a philosophical account of intrinsicality.) Weatherson claims that it is metaphysically possible for the instantiated perfectly natural properties to be vector properties. He then argues that, since vector properties must be extrinsic, it follows that at least some perfectly natural properties fail to be intrinsic, namely the perfectly natural properties instantiated at such worlds. The claim that vector properties need to be extrinsic, however, is highly contentious. It is natural to understand a vector property to be a property that is usefully represented for theoretical purposes by a certain kind of mathematical object, namely a vector. Given this construal, however, there is no reason to think that vector properties cannot be intrinsic. For example, due to the similarity relationships between colours represented by the colour solid it might be useful to represent colours by vectors. However, doing this is compatible with metaphysical theories of colour on which colours are intrinsic. There might be other conceptions of being a vector property on which vector properties cannot be intrinsic. However, it is unclear whether there an conception of vector properties on which they cannot be intrinsic, but can be fundamental. (See Busse (2009) and Marshall (2016b) for more discussion.)