ŚVETĀŚVATARA UPANISHAD · 5.8

अङ्गुष्ठमात्रो रवितुल्यरूपः संकल्पाहंकारसमन्वितो यः ।
बुद्धेर् गुणेनात्मगुणेन चैव आराग्रमात्रो ह्य् अवरो ऽपि दृष्टः ॥

aṅguṣṭhamātro ravitulyarūpaḥ saṃkalpāhaṃkārasamanvito yaḥ ।
buddher guṇenātmaguṇena caiva ārāgramātro hy avaro ’pi dṛṣṭaḥ ॥

That lower one also, not larger than a thumb, but brilliant like the sun, who is endowed with personality and thoughts, with the quality of mind and the quality of body, is seen small even like the point of a goad.