The first part of this work includes four original essays by Professor David Christopher Lane on the Darwin-Wallace debate, focusing on the contentious issue of whether or not natural selection can explain the human mind or soul.

In part two we have included the two original essays by Darwin and Wallace in 1858 concerning their discovery of evolution by natural selection as presented to the Linnean Society in London, England.

In part three we have incorporated brief biographies by James Marchant of Alfred Russel Wallace and Charles Darwin and their interactions with each other.

Finally the book ends with an excerpt from Alfred Wallace's questionable 1889 book, Darwinism, where he argues that the mechanism of natural selection is ultimately limited in its application. Darwin, on the other hand, argued persuasively that natural selection could indeed explain human cognition and morality. On this crucial point, Darwin and Wallace, though still remaining friends, forever departed company.