VACUUM, in philosophy, denotes a space empty or devoid of all matter or body.
It has been a matter of much dispute among philosophers whether there be in nature a perfect vacuum, or space void of all matter; but if bodies consist of material solid atoms, it is evident that there must be vacuities, or motion would be impossible (See METAPHYSICS, n° 193). We can even produce something very near a vacuum in the receiver of an air pump and in the Torricellian tube (see PNEUMATICS, passim); and it is very doubtful whether the particles of the densest bodies known be in perfect contact. See OPTICS, n° 63—68.