Aleksandar V. Božić delivered the talk “Probing the “grey area”: natural kinds and extraterrestrial life”. In his talk, Aleksandar dealt with the so-called “grey area” between nonlife and life, populated by entities of indeterminate aliveness, such as viruses. He analyzed an approach for determining the aliveness of the “grey area” entities in the context of a possible existence of natural kinds of such entities, with terrestrial and extraterrestrial instances. ISHPSSB Biennial Meeting 2021 was held online, July 13 – 20, 2021.

The conference program including the book of abstracts can be found below.