Hiroshi Ishiguro's Geminoids are so realistic they can almost pass for human — which is really cool or really creepy, depending on whom you ask.

These human reactions to his robotic creations are part of Ishiguro's research.

He created the Geminoids — including one that closely resembles him — to study how people interact with robots and what differentiates us from machines.

"My goal is to understand what human is," he told The Global Mail. "By making a copy of a human, I think we can understand humans."

Ishiguro, an Osaka University professor, has been developing robots for more than 20 years, and he recently shared some of his creations during a press preview at the National Museum of Emerging Science and Technology in Tokyo.

During the demonstration, the remote-controlled androids moved their lips in time to a voice-over, tilted their heads, blinked and gestured.

Although there were glitches — such as when one robot failed to introduce itself when asked to do so— Ishiguro's Geminoids impressed their human audience with how closely they resembled them.

Ishiguro believes that robots and androids will not only one day be part of mainstream society, but also that humans will form relationships with them — an idea that can seem creepy or downright wrong to some.

"All of my staff have formed a relationship with and become very attached to the androids they have been developing," he said in an interview with Engineering & Technology Magazine.

Ishiguro says what it comes down to is whether we believe such man-made creations have a soul.

"In Japanese culture we consider everything has a soul," he said. "We never distinguish between humans and others. But in Europe and the United States, especially for Christians, they believe that only humans can have a soul, so that is the difference between humans and others."

He says that robots are simply an extension of computers, technology that people once saw as potentially dangerous.

In fact, by combining technology and humanity and building robots, Ishiguro says we're "projecting the human soul."

He thinks robots can become human social partners — it's all just a matter of belief.

"[My goal is] for a human to become believably affectionate towards a robot social partner. Belief is the single most important aspect of a human being. You believe that I am a human, right? The human brain is just guessing, perceiving and believing. Everything is just a kind of illusion, or a trick, because the human brain cannot process everything. Everything is subjective."

Learn more about Ishiguro and his robots in the video below.

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