The lie that exalts us is dearer than a thousand sober truths.
Alexander Pushkin
The fear that death is the terminus of individual existence motivates a wide range of ideationally inconsistent models. These include the belief that humans are a separate creation from the rest of life — not least because it is very easy to believe that other organisms, such as fish, grass and bacteria do not proceed to a new life after death.
This fear is especially evident in models of mind and consciousness that are largely consistent with older concepts such as soul and spirit. On the one hand, mind and consciousness are used to demarcate a dividing line between humans and other species. On the other hand, by modelling mind and consciousness as things, it is possible to model them as composed of an immaterial substance which is not subject to material death.
This fear is understandably deep, since animals with a high value for self-preservation are more likely to survive and reproduce than animals without. Natural selection would favour any genes whose expression contributed to such a basic value, and the value has been a powerful selector of the types of models that have evolved from prehistoric times.