The discovery that the DNA of chimpanzees and humans is incredibly similar, sharing 98% of the same code, suggests that there is very little different--or special--about the human animal. Likewise, advances in artificial intelligence mean that humans no longer have exclusive access to reason, consciousness and imagination. Indeed, the harder we cling to the concept of humanity, the more slippery it becomes. But if it breaks down altogether, what will this mean for human values, human rights, and the defense of human dignity? In a book of breathtaking range, Felipe Fernandez-Armesto takes us on an enlightening journey through the history of humankind, a narrative tour de force that challenges our most fundamental belief--that we are, and have always been, human. Humankind confronts the problem from a historical perspective, showing how our current understanding of what it means to be human has been shaken by new discoveries from science and philosophy. The author shows how our concept of humankind has changed over time, tracing its faltering expansion to its present limits and arguing that these limits are neither fixed or scientifically verifiable. Controversially, he proposes that we have further to go in developing our concept of humankind and that we need to rethink it as a matter of urgency. One of the most imaginative historians writing today, Felipe Fernandez-Armesto here combines astonishing breadth with passionate and exciting storytelling.