The works of Ādi Śaṅkarācārya

Sanatsujātīyam

p. 212

p. 212

विज्ञानं परमार्थोऽसौ द्वैतिनोऽतथ्यदर्शिनः ।

In plain words

Consciousness itself — that is the highest reality. Those who insist on two are seeing what is not so.

Close to the Sanskrit

Consciousness — that is the supreme reality; the dualists are seers of the untrue.