Are we a unique species on a unique planet? - or just the ordinary Galactic standard?

Are we a unique species on a unique planet? A conference bringing together world leading scientists in the area of astronomy, biology, chemistry and philosophy to discuss our place and future in the universe – are we the most intelligent lifeform in the Galaxy, maybe the only one, or does all Earth-like exoplanets promote intelligent life similar to us, or even far beyond our imagination?