Voltaire was not a sportswriter. But he might well have had spring training in mind when he wrote the line that is appropriated above. For it would indeed be hard to improve on the world that baseball creates each spring in the sunshine (well, mostly sunshine) of Florida and Arizona. Optimism runs high, and the euphoria is so thick that you can cut it with a fungo bat. To capture the spirit of this unique little world, SPORTS ILLUSTRATED sent Artist Marc Simont on a tour of the training camps, and the incomparable results of his journey include the cover for this week's issue and the portfolio of perceptive paintings on this and the following pages. Although, as Pitcher Jim Brosnan confides on page 62, there are certain anxieties among the players, perhaps typified by the veteran nursing an aging soupbone in the sketch above, Artist Simont found the prospect a generally happy one: young men aglow with health and vigor, old folks watching them at the ball park and in the hotel lobbies, smiling and serene; young and old blissfully forgetting for a while that somebody's got to finish eighth. Nobody around the training camps, according to Simont, appears to be middle-aged.