Uploading one’s mind onto a computer seems like the stuff of science fiction, but it is an idea that has a few prominent believers buying into it. Chief among them is Tesla CEO Elon Musk.

In an interview with Business Insider on March 26, Musk said that he believed it was completely possible to reach a point in the future where the human mind could be uploaded onto a computer.

“I think it is possible,” Musk told Insider. “Yes, we could download the things that we believe make ourselves so unique.

But how exactly would this work? Exactly what constitutes consciousness remains an open philosophical question. Even if that answer was clearer, it remains unclear how the mind can be extracted from neurons and planted onto a computer. But despite the gaps in both understanding and technology available before this is ever possible, the idea of uploading a person’s mind online has some prominent believers who predict ways it can be possible.

One way to do this is to theoretically create memories from data that already exists about a person. In his interview, Musk suggests that digital memories - such as photos and digital communications - can serve as a basis for preserving a person’s personality digitally.

“Our memories are stored in our phones and computers with pictures and video,” Musk explained. “Computers and phones amplify our ability to communicate, enabling us to do things that would have been considered magical...We’ve already amplified our human brains massively with computers.”

Some proponents of the idea take this a step further. Dmitriy Itskov, a Russian billionaire and subject of a BBC documentary called “The Immortalist”, has supported a project known as the 2045 Initiative that bills itself as a vehicle moving towards humanity’s next stage of evolution.

The name 2045 comes from a tentative timeline on the project’s website that lays out their goals for achieving “neo-humanity”. According to it, the project aims to create an autonomous system that links the human brain to a robot "avatar" that can be used for those whose bodies are "worn out" or "irreversibly damaged" by 2025. By 2035, it projects that a computer model of the brain and consciousness will be created for the avatar and new bodies will be crafted for these artificial minds by the year 2045.

Istkov explains his goals as motivated by a desire to make sure that “we can all live forever." The 2045 Initiative has partnered with a number of technologists and researchers worldwide to make this vision a reality, but it is unclear what progress it has made to this end since it launched in 2011.

But the avatar model proposed by Itskov is one that has been embraced by others too.

Michio Kaku, a theoretical physicist at the City College of New York, has also said that it is possible "in principle" to transfer consciousness at some point in the future. In an interview with the Big Think from December 2020, Kaku suggested that a digitized mind would be uploaded into an avatar as Iskov suggested but added that the mind would then be something that can be “beamed” across the universe.

"I personally believe that one day we will digitize the entire human brain," Kaku explained in the interview. "This is all within the laws of physics."

But even if it is possible to upload the mind to a computer, a series of philosophical questions then follow. Would it still be you? Are we still conscious within a computer? Is it even right for everyone to live forever?

Elon Musk has his own answer to at least one of these questions; immortality may not be for everyone or desirable for evolution.

“I don’t think we should try to have people live for a really long time,” Musk said in his interview with Insider. “That would cause asphyxiation of society because the truth is, most people don’t change their mind. They just die. So if they don’t die, we will be stuck with old ideas and society won't advance.”