Rational Self-Love
Self-preservation and self-care are natural and good, provided they serve virtue rather than ego gratification.
Stoics taught oikeiōsis — a natural affiliation or self-preservation drive — as the root of both self-care and other-care. One naturally attends to oneself, then extends this care to family, community, and finally all humanity. Rational self-love is thus the seed from which universal benevolence grows.
We are not born for ourselves alone.
Stoic oikeiosis anticipates evolutionary accounts of altruism beginning with kin selection and extending to universal moral concern.
De Officiis