Vitarka Mudra is the gesture of argument. In this gesture the tips of thumb and index finger touched forming a circle. All the other fingers are extended upwards. The arm is extended all way down with palm facing outwards, fingers extended downwards. This is the Mudra of Dhyani Buddha Ratna Sambhava, Avalokiteswara, sometimes, of a standing Sakyamuni. This is the mystic gesture of Taras and Boddhisatwas.