“A delightful theory!” she exclaimed. “I must put it into practice.”

“A dangerous theory!” came from Sir Thomas’s tight lips. Lady Agatha shook her head, but could not help being amused. Mr. Erskine listened.

“Yes,” he continued, “that is one of the great secrets of life. Nowadays most people die of a sort of creeping common sense, and discover when it is too late that the only things one never regrets are one’s mistakes.”

A laugh ran round the table.