The scales of Justice – they don’t weigh eye-to-eye or rewards and punishment. The sword represents a higher purpose. The scales show us that the burden of our innocent ignorance is weighed against the fruit of knowledge’s heavy guilt. Each scale is empty and ready to weigh this duality. This card ultimately represents opposite forces. The woman is feminine power at a superhuman level. Her sword represents the masculine, as well. These two scales are held together by a bar so that they can function in friendly opposition.
The sword is held upright like a scepter – one must accept the full responsibility of knowledge – both good and evil. It also helps us to separate fantasy from reality, and this discrimination eliminates confusion and false images to find the truth.
This is the balance of the vertical (sword) and horizontal (scales) lines to form the cross of human limitation versus striving towards spirit, and of practicality versus idealism. She is the mediator between realities.
Source: Jung and Tarot: An Archetypal Journey, by Sallie Nichols