It is argued that if extraterrestrial intelligent beings exist, then their spaceships must already be present in our solar system.

— Frank J. Tipler Extraterrestrial intelligent beings do not exist (1980)

More quotes by Frank J. Tipler

The Physics of Immortality (1994)

The Physics of Immortality (1994)

Extraterrestrial intelligent beings do not exist (1980)

The Physics of Immortality (1994)

Extraterrestrial intelligent beings do not exist (1980)

Quote text and notes from Wikiquote: Frank J. Tipler (page history), available under CC BY-SA 4.0. Source quality and labels are our own summary of what Wikiquote records.