A variation on the posthuman theme is the notion of a "posthuman god"; the idea that posthumans, being no longer confined to the parameters of human nature, might grow physically and mentally so powerful as to appear possibly god-like by human standards. This notion should not be interpreted as being related to the idea portrayed in some science fiction that a sufficiently advanced species may "ascend" to a higher plane of existence—rather, it merely means that some posthuman beings may become so exceedingly intelligent and technologically sophisticated that their behaviour would not possibly be comprehensible to modern humans, purely by reason of their limited intelligence and imagination. The difference here is that the latter stays within the bounds of the laws of the material universe, while the former exceeds them by going beyond it.