One (philosophy)
One was a philosophical concept utilized within Doctor Sevrin's movement in the mid-23rd century. Spock was familiar with the idea. According to Sevrin, he and his group were One. Outsiders might also be One, and if they were they would understand his group's purpose. This purpose was to turn their backs on confusion and seek the beginning, Eden. 

Upon the revelation that doctor Sevrin was a carrier for Synthococcus novae and any primitives on the planet he sought would be heavily hit by the disease, Sevrin claimed that he intended to become One with them to both cure his disease and build " a world such as this galaxy has never seen" together.

Spock held great respect for Sevrin's movement, and one member, Adam, felt at one point that he was practically One. ()

See also
Herbert; another concept in Sevrin's philosophy

Philosophy