Ingabe zikhona izidalwa ezingaziwa?
Nakuba bungekho ubufakazi obucacile bokuthi kukhona ukuphila okukhona ngaphandle komhlaba, inani elikhulu lamaplanethi okungenzeka likhona endaweni yonke lisikisela ukuthi, nakuba kungase kube nzima ukuqala ukuthuthukiswa kokuphila, kufanele kube khona ezinye izinhlobo zokuphila endaweni yonke.  Ukungafani phakathi kokulindela ukuba khona kokuphila endaweni yonke nokuntuleka kwanoma yibuphi ubufakazi kubizwa ngokuthi i-Fermi-Paradox.