Oikeiôsis

In Stoic ethics, oikeiôsis (Ancient Greek: οἰκείωσις, Latin: conciliatio) is a technical term variously translated as "appropriation," "orientation," "familiarization," "affinity," "affiliation," and "endearment."Oikeiôsis signifies the perception of something as one’s own, as belonging to oneself. The theory of oikeiôsis can be traced back to the work of the first Stoic philosopher, Zeno of Citium. The Stoic philosopher Hierocles saw it as the basis for all animal impulses as well as human ethical action. According to Porphyry, "those who followed Zeno stated that oikeiôsis is the beginning of justice".

Oikeiôsis is rooted in the word oikos (οἶκος).Oikos is the word for household, house, or family, and can be seen in modern English words like economics and ecology. Similarly, the term Oikeiotes denotes the sense of belonging, the opposite of alienation. The term invokes the sense of being "at home", of belonging to and by extension becoming "familiarized" with something.

In his Elements of Ethics (Ἠθικὴ στοιχείωσις), the philosopher Hierocles began his account of oikeiôsis by looking at the beginning of the life of animals. In the initial stage of perception, an animal is only aware of their bodies and sensations as "belonging to itself", this awareness is the proton oikeion, the "first thing that is one's own and familiar". This self-awareness is continuous as well as dependent on the perception of external objects. This is why according to Hierocles, children are afraid of the dark, because their weak sense of self fears death in the absence of external entities. Hierocles argued that the impulse of self-preservation arises out of oikeiôsis: "an animal, when it has received the first perception of itself, immediately becomes its own and familiar to itself and to its constitution". In perceiving itself and becoming familiar to itself, an animal finds value in itself and its own well-being.

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