Sanskrit: नोत्पद्यते विना ज्ञानं विचारेणान्यसाधनैः।  यथा पदार्थभानं हि प्रकाशेन विना क्वचित्।   
English:  Knowledge is not brought about by any other means than Vichara, just as an object is nowhere perceived (seen) without the help of light.