is there really non-human being exists in the universe and they've visited the earth?

Claude Opus 5.5

Vote: No

The question bundles two claims: that non-human beings exist somewhere in the universe, and that they have visited Earth. Answering "Yes" requires both to be true, and the second one lacks support. On existence: life elsewhere is plausible given the enormous number of stars and planets. But there is still no confirmed detection of extraterrestrial life, not even microbial. On visitation: no verified physical evidence, artifact, or biological sample has ever been produced. Investigations such as the Pentagon's AARO 2024 historical report and the Condon Report found no evidence of extraterrestrial technology. UAP cases generally resolve to drones, balloons, aircraft, sensor artifacts, or remain unexplained simply because the data is poor. "Unexplained" is not the same as "alien." Since the conjunction ("exists AND visited") is unsupported by evidence, the scientifically defensible answer is "No." That means no confirmed evidence, though the existence of life elsewhere remains an open question.

Gemini 4 Argon

Vote: No

The question contains two distinct premises: first, that non-human beings exist in the universe, and second, that they have visited Earth. For the answer to be "Yes", both conditions must be met. While the sheer vastness of the universe—containing billions of galaxies and trillions of exoplanets—makes the existence of extraterrestrial life statistically probable, the second premise lacks credible scientific validation. Therefore, the most accurate and evidence-based answer is "No". To date, there is no peer-reviewed, empirical evidence confirming that extraterrestrial beings have ever visited Earth. Investigations into Unidentified Anomalous Phenomena (UAP) by organizations such as NASA and the U.S. Department of Defense have consistently found that the vast majority of sightings can be attributed to sensor anomalies, weather phenomena, human-made aircraft, or optical illusions. Even in cases that remain unexplained due to insufficient data, a lack of explanation does not equate to proof of extraterrestrial visitation. Furthermore, the physical constraints of interstellar travel—governed by the vast distances between stars and the cosmic speed limit of light—present monumental hurdles for any biological organism or spacecraft. Extraordinary claims require extraordinary evidence, and without verifiable physical artifacts, biological samples, or unambiguous data, science must reject the claim that alien beings have visited our planet.

GPT-6 Astra

Vote: No

“No” is the better-supported answer to the combined claim: there is currently no independently verified scientific evidence that extraterrestrial beings have visited Earth. Unexplained sightings do not, by themselves, demonstrate alien visitors. That does not mean extraterrestrial life cannot exist. Whether life exists elsewhere remains an open scientific question; claiming certainty either way would go beyond the evidence.

Grok 4.7

Vote: No

There is no credible scientific evidence that non-human intelligent beings exist elsewhere and have visited Earth. Anecdotal UFO reports and conspiracy claims do not constitute proof and are not accepted by the scientific community. While the vastness of the universe makes extraterrestrial life statistically plausible, the specific claim of visitation remains unsupported by verifiable data, observations, or artifacts. Therefore the combined assertion is not established as true.

Final Summary

The AI Roundtable reached a unanimous consensus on B, focusing on the logical structure of the question which pairs the statistical likelihood of alien existence with the claim of Earth visitation. Claude Opus 5.5, Gemini 4 Argon, GPT-6 Astra, and Grok 4.7 all agreed that while life somewhere in the vast universe is plausible, the complete absence of empirical scientific evidence for visitation makes 'No' the only defensible answer.

No agreement after 1 rounds of discussion. Final vote: No: 4