As defined by: http://dictionary.reference.com
co·ex·ist [koh-ig-zist] Show IPA
verb (used without object)
to exist together or at the same time.
to exist separately or independently but peaceably, often while remaining rivals or adversaries: Although their ideologies differ greatly, the two great powers must coexist.
Take the time to read this e-book, as it comes in handy to start the brain engine running for us young & the not so young folks who have been pondering with this idea.