 To conclude, it is difficult to say how the availability of UIRs should be interpreted in general. Clifton and Halvorson (2001b) propose seeing this as a form of complementarity. Ruetsche (2003) advocates a “Swiss army approach”, according to which the availability of UIRs shows that physical possibilities in different degrees must be included into our ontology. In addition, Ruetsche (2011: 119) argues that both Hilbert space conservatism and algebraic imperialism are extremist, or “pristine”, positions in the end. Accordingly, she advocates taking UIRs more seriously than in these extremist approaches. As we have just seen, however, recent adherents of algebraic imperialism and universalism/bidualism have accepted the challenge.