The Vulcan mind meld or mind probe was a telepathic link between two individuals. It allowed for an intimate exchange of thoughts, thus in essence enabling the participants to become one mind, sharing consciousness in a kind of gestalt. (TOS: "Dagger of the Mind" ; TNG: "Sarek" ; et al.) Normally, it was employed only by Vulcans. It was a deeply personal thing, part of the private life, and generally not used on aliens. (TOS: "Dagger of the Mind" ) However, cases were known where the mind meld was initiated between a Vulcan and a non-Vulcan. (VOY: "Meld"; TNG: "Sarek" )