Picardy third
A piece in minor ends on a major triad — a sudden brightening at the last moment.
What it means
One speaks of a Picardy third when a piece or a section in minor closes on a major triad. The third of the closing chord is raised, so that the minor tonic becomes a major tonic. The effect is a sudden brightening exactly at the last moment.
Musical use
This procedure was widespread especially in the music of the sixteenth to eighteenth centuries, where minor pieces very often ended on a major sonority. A common explanation points to acoustics: the major third appears earlier in the harmonic series than the minor one, and the major triad counted as the more perfect, calmer closing sonority. The minor third above the lowest note, moreover, rubs against the overtones of the bass, which stands out especially in reverberant rooms. Alongside this, closing sonorities occur entirely without a third, which leave the mode open.
In later music the Picardy third becomes rarer and is used more deliberately; there it often works as an expressive turn — as consolation, a turn toward the light, or a surprising reconciliation at the end of a serious piece.
The origin of the name is not securely established; the explanations offered for it are unattested, and the designation has become established independently of them.
The Picardy third is to be distinguished from a change to the tonic major, which concerns a whole passage: here only the last sonority is brightened, the piece itself remains in minor.
The origin of the name is unclear; it is attested since Rousseau in the eighteenth century. In the music of the Renaissance and the Baroque, a major close to a minor piece is the rule, because the major third in the closing chord counted as more stable. Later composers used the turn deliberately, to express consolation or brightening at the end.
Performance practice
Watch, in the notation, for the accidental in the closing chord — it is easily overlooked, because the ear expects the minor close. Do not intonate the raised third too high; it should sound calm, not glaring. And do not shape the close as an effect: the effect lies precisely in its arising without emphasis.