"After I give lectures-on almost any subject-I am often asked, "Do you believe in UFOs?" I'm always struck by how the question is phrased, the suggestion that this is a matter of belief and not evidence. I'm almost never asked, "How good is the evidence that UFOs are alien spaceships?""

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Russia and the U. S. have announced they are definitely planning several space machines. So it's quite possible that the first space ships or satellites may encounter other interplanetary machines, manned or otherwise. Our space devices may even be closely approached by such alien machines.

— Donald Keyhoe