What are “natural kinds”? ... What the former planet Pluto can teach us about natural kinds ... Massimo’s changing views on theoretical entities ... Is there a paradigm shift on the horizon in evolutionary biology? ... Is skepticism toward natural kinds the same as skepticism toward essential properties? ... Why Massimo is skeptical of the concept of "laws of nature" ... Describing “ultimate reality” ... Can we distinguish between sex and gender without natural kinds? ... Can we have a conception of “normal” without natural kinds? ...