兼听则明，偏信则暗

jiān tīng zé míng , piān xìn zé àn

listen to both sides and you will be enlightened; heed only one side and you will remain ignorant (idiom)

兼

jiān

double

听

tīng

to listen to; to hear

则

zé

(literary) (conjunction used to express contrast with a previous clause) but; then

明

míng

bright

，

偏

piān

to lean

信

xìn

letter

则

zé

(literary) (conjunction used to express contrast with a previous clause) but; then

暗

àn

(literary) to close (a door)