 Also Op Art in the early 1960s had a powerful effect on him.Indeed, Op proved to be a strong predecessor to what he is calling Virtual Art in that Op Art called attention to the spectator's individual, constructive, and changing perceptions - and thus called upon the spectator to transfer the creative act increasingly upon him or herself.Op beckons forth a consideration of the enlargement of the audience's participatory role; both in regard to the perception of meaning and actual physical changes to the work of art.