The Roman Lady Justice, Iustitia held a sword in one hand, a balance scale in the other, and had her eyes blindfolded to signify the pursuit of equal justice.  In the face of war-hungry and sinful humankind, only Iustitia continued to preach about virtue and goodness, yet people still befell to the injustices of war.  In the end, even Iustitia gave up and returned to the heavens.  The balance scale that she put down at her feet thus became the constellation Libra.