Mahāprajñāpāramitā Sūtra

...the purity of all sensations born from the condition of eye-contact is the purity of that which is produced by the mind. Why? Why? The purity of that which is produced by the mind and the purity of the form-element up to all sensations born from the condition of eye-contact are non-dual, without two divisions, undifferentiated, and unbroken. Subhuti, the purity of that which is produced by the mind is the purity of the ear-element. The purity of the ear-element is the purity of that which is produced by the mind. Why? Because the purity of that which is produced by the mind and the purity of the ear-element are non-dual, without two divisions, undifferentiated, and unbroken. The purity of that which is produced by the mind is the purity of the sound-element, the ear-consciousness element, and ear-contact, as well as all sensations born from the condition of ear-contact. The sound-element up to all sensations born from the condition of ear-contact is the purity of that which is produced by the mind. Why? Because the purity of that which is produced by the mind and the purity of the sound-element up to all sensations born from the condition of ear-contact are non-dual, without two divisions, undifferentiated, and unbroken. Subhuti, the purity of that which is produced by the mind is the purity of the nose-element. The purity of the nose-element is the purity of that which is produced by the mind. Why? Because the purity of that which is produced by the mind and the purity of the nose-element are non-dual, without two divisions, undifferentiated, and unbroken.