Vaisesika Sūtra 2.2.17

सामान्यप्रत्यक्षाद् विशेषाप्रत्यक्षाद् विशेषस्मृतेश्च संशयः ॥१७॥

sāmānyapratyakṣād viśeṣāpratyakṣād viśeṣasmr̥teśca saṁśayaḥ ॥17॥

[सामान्य (sāmānya): General; प्रत्यक्ष (pratyakṣa): Perception or direct observation; आत् (āt): From; विशेष (viśeṣa): Specific or particular; प्रत्यक्ष (pratyakṣa): Perception or direct observation; आत् (āt): From; विशेष (viśeṣa): Specific or particular; स्मृति (smṛti): Memory; इष् (iṣ): From; च (ca): And; संशय (saṃśaya): Doubt or uncertainty;]

During the direct perception of generality and the direct perception of speciality, only the speciality is remembered, resulting in doubt.