Conventional baseball wisdom is that the hitter with the best eye is the one who takes the most walks. But Braves first baseman Freddie Freeman—who was far from the league lead in that category last year—may in fact be baseball's most discerning hitter.

When it comes to deciphering balls from strikes, no one tops Freeman, who hit .319 with 23 homers and 109 RBI. He only took about one strike a game, but that doesn't mean he swings at everything. Freeman took nearly five times as many balls per plate appearance as strikes,...