egoism

The word 'egoism' is a modern philosophical term constructed from classical components. Its first element, 'ego', is the Latin first-person pronoun meaning "I", which can be traced back to the Proto-Indo-European root éǵh₂, also meaning "I". The second element, '-ism', entered English via Latin from the Greek suffix '-ismos', used to form nouns of action or practice. The compound was formed in the late 18th century to name the ethical theory that bases morality on self-interest. The logic of the word is transparent: it literally denotes the "doctrine of the self," where one's own welfare is the primary or sole good, evolving from the concrete concept of "I" to an abstract philosophical principle centered on the self.

Structure: ego (self) + ism (doctrine or belief) - ego: From Latin 'ego' meaning "I, myself". It functions as the core root denoting the self. - ism: From Greek '-ismos', a suffix forming nouns of action or practice, later denoting distinctive doctrines, systems, or theories. It functions as a noun-forming suffix indicating a belief system or principle.