A skull – a human who is destroyed, completely worn-out. It is an empty place left behind an individual consciousness, which used to fill tightly this small bony case. It is a bit ridiculous and at the same time how really sublime it is. It seems that there is nothing else paralelly comic and horrid, admirable and at the same time pathetic.
For visual arts a skull is a quasi founding motive. It appeared a long time before “art history” (the Jericho masks), when it embodied spirits of the dead and made them visually present. It became popular in Early Modern iconography, especially in Baroque, although already in Renaissance a protest against a cemetery was hidden behind an invention of a portrait, following Hans Belting's words. A skull is a reverse of a portrait – life hides death just like a face hides a skull as long as the latter emerges to manifest the need of faith in an immortal soul which cannot be depicted otherwise. Similarly, it is impossible to depict self which is being disintegrated at the moment of death (Belting, Faces, p.137).
Death is a problem, it is obvious, perhaps even the biggest one. The ancient Stoics' rationalisation won't help: as long as I am – there is no death, when it comes – I am not here anymore. For some people it may also come as consolation: “Neither living here, nor dead there” reads the inscription on one of the graves in church Santa Maria del Popolo.