Vaisesika Sūtra 4.1.10

तस्याभावादव्यभिचारः ॥१०॥

tasyābhāvād avyabhicāraḥ ॥10॥

[तस्य (tasya) - of that; अभावात् (abhāvāt) - due to absence; अव्यभिचारः (avyabhicāraḥ) - non-deviation (consistency);]

Its (conjunction of substances) absence results in 'avyabhicāraḥ', i.e. non-deviation, i.e. uniformity.