Let P be a point, A'B'C' its pedal triangle, A”B”C” the circumcevian triangle of P with respect to A'B'C'..Let ra be the radical axis between the circles with diameters B'B”,C'C”; define analogously rb, rc. The parallels from A, B, C to ra, rb, rc concur at the isogonal of the infinite point of the line PP*, P* being the isogonal of P.