In British post-World War II musicology, 'progressive tonality' was sometimes contrasted with 'regressive tonality' (e.g. in the analytic and critical writings of Hans Keller). The distinction was not one of chronological or stylistic 'advancedness', but rather a means of distinguishing between tonal motions that could either be reckoned as 'up' or 'down' around a circle of fifths construed as intersecting with the original tonic. By this measure, Mahler's 4th Symphony would exhibit 'progressive tonality' (it begins in G and ends in E, three fifths 'higher')—while the same composer's 5th Symphony would display 'regressive tonality' (it begins in C and ends in D, five fifths 'lower').