Both Thomas Talbott and Friedrich Schleiermacher have argued, in somewhat different ways, that in the context of Christian theism the damnation of anyone would render it impossible to extend genuine blessedness to anyone else. I examine both Schleiermacher's and Talbott's version of this argument, which I call the ‘incompatibility argument', and respond to criticisms levelled by Jerry Walls and William Lane Craig. I argue that the argument is more powerful than its critics admit, and that it poses a potentially devastating challenge to what Thomas Talbott calls ‘moderately conservative theism', according to which the damned autonomously choose their own damnation by forever rejecting God's offer of salvation.