The paper discusses the philosophical thinking of Egon Bondy in the context of the Czechoslovak underground community, which was formed in the 1970s. It argues that Bondy's non-substantial ontological model as well as his visionary reflections and theses concerning the emergence of post-biological and artificial beings (which later became the basic theme of the international transhumanist movement) represent a pioneering and crucial effort by setting a new direction both in the domestic and international philosophical and cultural discourse. However, Bondy transcends the limits of transhumanism and his concerns eventually lead him to the postulates of posthumanism. The essay then interprets Josef Šmajs's model of evolutionary ontology as a certain "echo" of Bondy’s lifelong ontological project. It further demonstrates that despite the existential urgency of issues concerning the meaning of human existence or systemic solutions to the global ecological crisis, both ontological models are currently excluded from current mainstream philosophical reflection and criticism. The paper thus discusses various sources of such negligence and offers a platform and a starting point for further development of both philosophical concepts.