 Yagisawa’s extended modal realism proposes a Lewis-inspired realist account of impossible worlds and impossibilia (the objects exemplifying absolute impossibilities which inhabit impossible worlds). On this view, impossible worlds are concrete mereological sums of real individuals, which are causally and spatiotemporally interrelated within each world but never across worlds (see Yagisawa 1988). Yagisawa exploits the “argument from ways” we met above: if quantification on ways the world might be or have been commits us to possible worlds, then, by parity of reasoning, quantification on ways the world might not be commits us to impossible worlds. The argument is backed by Yagisawa’s considerations on the additional logical and philosophical applications allowed by impossible worlds, which are not available, in his view, to traditional Lewisian modal realism. Extended modal realism is a strong position: concrete impossible worlds represent absolute and logical impossibilities directly, by instantiating them. So impossibilities and, in particular, logical inconsistencies, are “out there” in reality.