The first and most constructive criticism Boltzmann received was from his friend and mentor Josef Loschmidt. The latter’s motivation was that he disliked the way the second law of thermodynamics predicted that the universe would eventually die, degenerating into a never-changing state in which all heat had dissipated throughout the cosmos. If this was true, wrote Loschmidt, the second law is a “terroristic nimbus cloud, which appears to be a destructive principle to all life in the universe.”
