So it was with Dénes Várjon, whose local debut Thursday at the American Philosophical Society was a configuration of repertoire whose components weren’t unknown but converged into an overall experience that went to harrowing places. […] Among his pianistic countrymen, Várjon is closer to Annie Fischer than to Andras Schiff. Várjon’s unvarnished treatment of harmony and aggressive rhythm give an imperative impetus and sense of occasion to whatever he does. Yet when Beethoven seems at his most impulsive and Janacek at his most explosive, Várjon found interlocking seams that suggested how such contrasting ideas belonged together. And he did so without smoothing down anything or minimizing flashpoints. Such is the work of a major pianistic personality.