  This paper proposes a model which aim is providing a more coherent framework
for agents design. We identify three closely related anthropo-centered domains
working on separate functional levels. Abstracting from human physiology,
psychology, and philosophy we create the $P^3$ model to be used as a multi-tier
approach to deal with complex class of problems. The three layers identified in
this model have been named PhysioComputing, MindComputing, and MetaComputing.
Several instantiations of this model are finally presented related to different
IT areas such as artificial intelligence, distributed computing, software and
service engineering.
