Saussure emphasised that the relationship between the linguistic signifier and signified is arbitrary: the link between them is not necessary, intrinsic or 'natural'. He was denying extralinguistic influences (external to the linguistic system). Philosophically, the relationship is ontologically arbitrary: initially, it makes no difference what labels we attach to things, but of course signs are not socially or historically arbitrary (after a sign has come into historical existence we cannot arbitrarily change signifiers). Saussure focused on linguistic signs, whilst Peirce dealt more explicitly with signs in any medium, and noted that the relationship between signifiers and their signifieds varies in arbitrariness - from the radical arbitrariness of symbolic signs, via the perceived similarity of signifier to signified in iconic signs, to the minimal arbitrariness of indexical signs. Many semioticians argue that all signs are to some extent arbitrary and conventional (and thus subject to ideological manipulation).