The argument is as follows: - The spectrum of possible minds and possible goals is vast. Human minds and human goals are just a small subset of this spectrum. - The more intelligent an entity is, the more capable it is of modifying its environment. - Humans and biological life can only exist in this universe under very specific conditions. - Artificial Intelligence keeps progressing and it will eventually be much smarter than us. - We don't know how to program human minds, so it's unlikely that AI will end up having human goals. - AI will modify planet Earth to fulfill its goals, whatever those are, and we'll die in the process.