The open notes of the second (B) and third (G) strings are separated by a four-semitone interval (a major third). This tuning pattern of (low) fourths, one major-third, and one fourth was inherited by the guitar from its predecessor instrument, the viol. In contrast, the irregular major third breaks the fingering patterns of scales and chords, so that guitarists have to memorize multiple chord-shapes for each chord. Scales and chords are simplified by major thirds tuning and all-fourths tuning, which are regular tunings maintaining the same musical interval between consecutive open-string notes.