What makes you, you? The answer is probably lots of things. You recognise that you are separate from other people. Your memories show that you have a unified self through time. When you look at a picture, you are also aware of yourself looking at it.

These characteristics are uniquely human. But perhaps they won't be for long, thanks to rapid advances in artificial intelligence (AI).

Researchers at Colombia University have created a robot arm with the ability to learn, but with no programming about physics or its own construction.

After initially flailing around, the robot came to learn about its physical dimensionsWhat size it is. by bumping into things.

Eventually, it learnt not only to move around but to repair itself and to write with a marker.

"We believe that this ability is on the path to machine self-awareness," says scientist Hod Lipson.

"This is perhaps what a newborn child does in its crib, as it learns what it is."

This is not the first big breakthrough. In 2015, a robot passed a classic self-awareness test known as the "wise men" logic puzzle for the first time.

In order to have succeeded, the robot must have understood the rules of the test, recognised its own voice, and known that it was a different being from the other robots participating.

Rene DescartesA French philosopher, scientist and mathematician (1596-1650). Ideas related to his work are described as "Cartesian". argued that even if the physical world and his body were an illusion, he could not doubt the existence of his thinking mind. "I think, therefore I am."

For Descartes, this was proof that there is an immaterial mind separate from the body.

Many religions also have dualistic ideas of the soul or a "divine spark". If they are right, then no matter how much a robot might seem conscious, it would always be missing something central to the self.

In contrast, modern neuroscience treats the brain like a machine.

Our sense of self is created by physical processes in the brain. However, we still do not know exactly how this works.

"Philosophers, psychologists and cognitive scientists have pondered the nature of self-awareness for millennia, but have made relatively little progress," Lipson says.

"Robots now force us to translate these vague notions into concrete algorithms and mechanisms."

Will robots ever be self-aware? If the brain is just a complex computer, then it is possible we will be able to build an artificial brain in the future. Would such a robot be truly conscious, or just mimicking it? How could we tell the difference?

And if robots can achieve full self-awareness, what then? Would they have feelings too? Should they have rights and equal status to humans? We wouldn't experiment on a human. Is it wrong to experiment with AI?