 One might attempt to answer this question by first noting that it is much more common for philosophers to use Lewis’s second “in virtue” characterisation (or some variant of it), than either of the other two characterisations when explaining what they mean by ‘intrinsic’. (For example, as far as we know, Lewis uses the “in virtue” characterisation whenever he explains what he means by ‘intrinsic’, but only uses the other characterisations once.) This suggests that philosophers typically use ‘intrinsic’ to express a notion of interiority rather than either of the notions of locality or duplication preservation.