Vaisesika Sūtra 1.1.18

द्रव्यगुणकर्मणां द्रव्यं कारणं सामान्यम् ॥१८॥

dravya-guṇa-karmaṇāṁ dravyaṁ kāraṇaṁ sāmānyam ॥18॥

[द्रव्य-गुण-कर्मणाम् (dravya-guṇa-karmaṇām) - of substance, quality, and action; द्रव्यम् (dravyaṁ) - substance; कारणम् (kāraṇam) - is the cause; सामान्यम् (sāmānyam) - in common;]

The substance is the general cause of substances, qualities, and movements.