Gotamasutta

sn12.10:2.1 Then it occurred to me:

sn12.10:2.2 ‘When what exists is there old age and death? What is a requirement for old age and death?’

sn12.10:2.3 Then, through rational application of mind, I penetrated with wisdom:

sn12.10:2.4 ‘When rebirth exists there’s old age and death. Rebirth is a requirement for old age and death.’