。
The pen is mightier than the sword.
Literal
Letters/writing [topic-は] military-force [target-に] surpasses.
文は武に勝る is a proverb equivalent to 'the pen is mightier than the sword.' 文 (letters/learning/civil arts) and 武 (military/martial arts) are a classic pair in East Asian thought. 勝る means 'to surpass' or 'to be superior to.'