Note that different people have different research approaches. The two old ladies check that none of them can see herself and the problem is solved! ;-)
The other older lady makes an experiment with motion and rigorously determines that she is ... well ... unsichtbar. :-)
What An Earth-Like World Around Proxima Centauri Would (And Wouldn’t) Mean (Synopsis) - “To consider the Earth as the only populated world in infinite space is as absurd as to assert that in an entire field sown with millet, only one grain wil...
12 hours ago