Russell puts much weight on the concept of relation. In his view relations are real entities that are indispensable in the enterprise of defining mathematical objects, particularly numbers. In the paper I try to extend Russell’s idea beyond the domain of abstract entities. I make an attempt to show that the basic criterion of identity for concrete objects – the criterion of space‑time continuity – can be supplemented, whenever it appears inadequate, by taking into account some relations apart from those that are spatiotemporal. On this occasion I argue for the metaphysical impossibility of time travel and offer some resolutions of the classical paradoxes of identity: amoebas’ reproduction by fission or Theseus’ boat. With respect to relations I argue, against the radical separation of the self from its attributes, that there are essential attributes of the self that constitute its relatively stable individual essence.

The aim of this paper is to discuss the composition of Johanna Sinisalo’s novel The Core of the Sun by demonstrating how the author used excerpts of academic text to create the literary world of the novel. As the theoretical foundation, I will use Lubomír Doležel’s research introducing the theory of possible worlds in literary creation. The realia, possibilia, and the transworld identity of the fictional world of Sinisalo’s novel is analyzed on the basis of excerpts from dictionary entries and scientific articles used as world-building elements.