The earliest Chinese documents mentioning a crossbow were texts from the 4th to 3rd centuries BC attributed to the followers of Mozi. This source refers to the use of a giant crossbow between the 6th and 5th centuries BC, corresponding to the late Spring and Autumn Period. Sun Tzu's "The Art of War" (first appearance dated between 500 BC to 300 BC) refers to the characteristics and use of crossbows in chapters 5 and 12 respectively, and compares a drawn crossbow to 'might.'