The Compendium of Caraka 4.3.8_4

4.3.8_4

sato hyavasthāntaragamanamātrameva hi janma cocyate tatra tatra vayasi tasyāṃ tasyāmavasthāyāṃ; yathā-satāmeva śukraśoṇitajīvānāṃ prāk saṃyogādgarbhatvaṃ na bhavati, tacca saṃyogādbhavati; yathā-satastasyaiva puruṣasya prāgapatyāt pitṛtvaṃ na bhavati, taccāpatyādbhavati; tathā satastasyaiva garbhasya tasyāṃ tasyāmavasthāyāṃ jātatvamajātatvaṃ cocyate//

For birth is said to be merely the transition to another state of an existing entity at this or that age, in this or that state: just as, though semen, menstrual blood, and the living entity are already existent, there is no embryonic state before their conjunction, and that [state] arises from conjunction; just as, though that very man is already existent, fatherhood does not exist before [having] offspring, and that arises from offspring; likewise, the state of being born and the state of being unborn are predicated of that very existing embryo in this or that state.