Since Denys Wilkinson last year reopened the question of whether or not second‐class currents exist in the weak interaction (physics today, September 1970, page 17), a flurry of theoretical and experimental activity has occurred. And the waters are muddier than ever now. Second‐class currents are those that have the opposite behavior under G‐parity as first‐class currents. The G‐parity operation is the product of charge conjugation and charge symmetry (which rotates the isotopic spin through 180 deg).

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