Cogito, ergo sum : from an enthymeme to bioethics

The work analyzes the Cartesian expression “cogito ergosum” from the points of view of the traditional and the modern logics. The expression is shown to be an enthymeme with the major premise omitted. Two ways of the major premise interpretation are made clear: 1) as a conventional assertion (a most commonly accepted view among philosophers); 2) as a proposition containing an equivalence. It is shown that the equivalence of “thinking and being” assumed by Descartes has once opened up the logical-anthropological opportunity to proclaim as “non-existing” what does not think. The last assertion provides the basis of “Ratiofundamentalism”. The work demonstrates that the Cartesian enthymeme analysis concerns directly our understanding of the ontological status of man and is inseparable from the questions of biomedical ethics.