Once we find signs of alien life (well, if) we will have to grapple with a new question, presuming that they haven't made the first move: should we make contact?

Renowned physicist Michio Kaku has made himself clear on the topic over the years, stating that he believes we will find alien life, and if we do we should be wary of making contact. In a new interview with The Guardian, he has gone further, calling it a "terrible idea".

"Soon we’ll have the Webb telescope up in orbit and we’ll have thousands of planets to look at, and that’s why I think the chances are quite high that we may make contact with an alien civilisation," he told the

publication."There are some colleagues of mine that believe we should reach out to them. I think that’s a terrible idea. We all know what happened to Montezuma when he met Cortés in Mexico so many hundreds of years ago. 

For those that don't know, the Spanish forces - led by Cortés - slaughtered the unarmed Aztecs until “the blood of the warriors flowed like water”, which doesn't sound like an ideal outcome of the first contact with alien life. Kaku has expanded on the idea in the past, explaining that though he believes that alien life will mostly be peaceful - given that the signatures we are likely to find will be of civilizations thousands or perhaps millions of years in advance of us - that doesn't mean that we should risk announcing ourselves to the universe.

"We cannot take the chance," he said in 2018. "We should not try to advertise our existence to alien life in outer space because of the fact that we don’t know their intentions."

The danger, he believes, is not that aliens will be "evil" per se, but more that they might not care about us at all. He compared our position in the universe to that of a deer in the forest. While hunters in the forest pose a threat to deer, the real danger comes from developers who might pave over the forest and destroy their environment.

"In fact, if you read the novel War of the Worlds the Martians in HG Wells seminal novel were not evil in the sense they wanted to torture us and they wanted to do all sorts of barbaric things to humanity," he added. "No, we were just in the way."