Chop the garlic with the salt and rub to a paste with the side of a chef's knife. Transfer to a small bowl and whisk together with the vinegar. Let stand for 15 minutes. Whisk in honey, mustard, and pepper. Gradually whisk in oil until incorporated. Stir in chopped parsley.
To serve, arrange whole leaves of radicchio, Bibb lettuce, Belgian endive, arugula, and the parsley sprigs in a serving bowl. Drizzle with dressing.