The concept of Nature in Adam Smith's thought could be understood in three dimensions :By the concept of Author of Nature ,Adam Smith confirmed the Providence in natural law,upgraded theidea of Destinyin Stoics ,and brought retaliationintothe establishment of moral order .By the concept of Nature ,Adam Smith clarified the ontological principle of Nature as the natural elements of a sentimental faculty of man .By the concept of human nature ,sympathy is considered as the elementary moral mechanis m of justice in society ,in which impartial spectator would play an important role in situational iudgment .