The quality of goodness brings happiness; the quality of Darkness produces sorrow; and if these two combine with the quality of Ignorance then neither happiness nor sorrow is produced.
सुखस्पर्शः सत्त्वगुणो दुःखस्पर्शो रजोगुणः। तमोगुणेन संयुक्तौ भवतोऽव्यावहारिकौ॥