Sāṃkhya Kārikā verse 9

asat-akaraṇāt-upādãnagrahaṇāt sarva-saṃbhavā-abhāvāt |
śaktasya śakyakaraṇāt kāraṇabhāvāt-ca satkāryam ||

asat - unreal; wrongabhāva - non-appearance, non-existence, absence