In this startlingly original and persuasive book, Raymond Tallis shows that it is easy to underestimate the influence of small things in determining what manner of creatures humans are. He argues that the independent movement of the human index finger is one such easily overlooked factor. Indeed, not for nothing is the index finger called the "forefinger." It is the finger we most naturally deploy when we want to pry objects out of small spaces, but it plays a far more significant role in an action unique to us among primates: pointing.

Tallis argues that it is through pointing that the index finger made a significant contribution to the development of humans and to the creation of a human world separate from the rest of the natural world. Observing the ceiling of the Sistine Chapel and the hugely familiar and awkward encounter between Michelangelo's God and Man through their index fingers, Tallis identifies the artist's intuitive awareness of the central role of the index finger in making us unique. Just as the reaching index fingers of God and Man are here made central to the creation of our kind, so Tallis believes that the seemingly simple act of pointing, which is used in a wide variety of ways, is central to our extraordinary evolution.