One of them creates the qualities. The other does not create them. Though they are different from each other by nature, they are, however, always united.
सृजतेऽत्र गुणानेक एको न सृजते गुणान्। पृथग्भूतौ प्रकृत्या तौ सम्प्रयुक्तौ च सर्वदा॥