Chang Tsao was a bureaucrat during the T'ang dynasty who had suffered his share of political setbacks. After a series of demotions Chang Tsao found himself a minor official in Chung Chow.
But, as his official career was waning, Chang Tsao's fame as a master painter was spreading. Whenever he put brush to paper his genius would shine through, especially in landscape paintings, in which he excelled. In addition to his unsurpassed art, Chang Tsao had a unique way of painting pine trees. In one hand he would hold two brushes, as one brush was finishing the withered branches of the pine, the other was adding newly sprouting buds. His paintings breathed nature into whichever room they were hung. Everybody called his paintings "immortal works," and his style became known as "Two Brushes Painting Together."
Today, this expression is used to describe the simultaneous use of two separate tactics to reach a common end.
(Kirby Chien)