Everyman

Everyone is familiar with the scientific classification Homo sapiens. Homo oeconomicus has in recent years become common again, in spite of being plainly mutilated by his love of profit: 'Sovereign in tastes, steely-eyed and point-on in perception of risk, and relentless in maximisation of happiness' in the definition of the economist Daniel McFadden, who further observed that this specimen is a pretty rare species. The propensity to mutilate (mind as well as body) has itself produced the only half-joking Homo mutilans, the mutilating species.

There are of course heaps of other everyman taxonomies, a rhetorical habit that started as far back as Aristotle, with his Zoon politikon (state-building animal), although Zoon polemikon is often the more appropriate. Hannah Arendt revived the term Homo faber, first used by Benjamin Franklin, to create her sociological category of the toolmaker. Homo duplex has been adopted by many writers and thinkers including Buffon, Balzac, Conrad and Durkheim, who developed the notion to suggest how animal and social tendencies played themselves out in humans, and Iain McGilchrist in his scientific bestseller The Master and the Emissary makes cerebral duplicity the biological borderline along which the best and worst in human history has taken place.

Gabriel Marcel popularised the use of Homo viator to suggest man on his way to God, although the epithet had already been used by Aquinas in Summa Theologica to describe Christ: 'simul viator et comprehensor' - at once a traveller and an understander. The contemporary ...