According to Aristotle, who knew even less about baseball than Marilyn Monroe, courage consists mostly of knowing when to sidestep danger. Most baseball players would find the 245 pounds of Ted Kluszewski a danger well worth sidestepping every time. But John Orsino, a youthful rookie catcher for the San Francisco Giants, is no philosopher. When Big Klu, now an L.A. Angel, came galumphing toward home plate at full speed in Palm Springs last week, Orsino set his own 205 pounds foursquare (elbow, forearm, foot and knee) against the invasion and waited calmly while Kluszewski plowed in. Kluszewski and the legend that he is the strongest man in baseball were exploded together. Flat in the dust on his broad-beamed back, Klu was quietly informed that he was out.