September 13, 2011
If a robot is produced that behaves just like one of us in all respects, including thought, is it conscious or just a clever machine, asks Prof Barry C Smith, director of the Institute of Philosophy.
Human beings are made of flesh and blood – a mass of brawn and bone suffused with an intricate arrangement of nerve tissue. They belong to the physical world of matter and causes and yet they have a remarkable property – from time to time they are conscious.
Consciousness provides creatures like us with an inner life: a mental realm where we think and feel and have the means to experience sights and sounds, tastes and smells by which we come to know about the world around us. But how can mere matter and molecules give rise to such conscious experiences?
The 17th Century French philosopher, Rene Descartes, thought it couldn’t. He supposed that in addition to our physical make-up, creatures like us had a non-material mind, or soul, in which our thinking took place.
For Descartes, the non-material mind was uniquely human. He denied that animals had minds. When they squealed with what we considered to be pain this, he thought, was just air escaping from their lungs. Animals were mere mechanisms. And even if we created a clever mechanical doll that replicated all our movements and reactions, it would not be capable of thinking because it would lack the power of speech.