1520s, "meet, meet in argument," from French occurrer "happen unexpectedly" or directly from Latin occurrere "run to meet, run against, befall, present itself," from ob "against, toward" (see ob-) + currere "to run" (from PIE root *kers- "to run"). Sense development is from "meet" to "present itself" to "appear" to "happen" ("present itself in the course of events"). Meaning "to come into one's mind" is from 1620s. Related: Occurred; occurring.
"faculty of the immediate introspection of the soul by itself," 1670s, from self- + perception.
in reference to things, "destroy itself automatically;" see self- + destruct, apparently first attested in the U.S. television series "Mission Impossible" (1966). Self-destructive "having the property of annulling itself" is recorded from 1650s, and self-destruction "destruction of oneself, suicide" is attested from 1580s; self-destroying (n.) is from 1610s.