The thesis of this book – namely, that Darwinism bred an influential tradition of non-violence – is hardly congruent with the familiar textbook scenario that Darwin's theory unleashed primarily harsh and divisive, conflict-based social doctrines. These were seen to apply both in the domestic arena of paupers, workhouses and laissez-faire politics, and in the global arena of clashing nation-states, empires and races

However, that orthodoxy has been under siege for some time. Recent scholarship has recognised that Darwinism generated social and political rhetorics and idioms that could readily be translated into a bewildering kaleidoscope of discourses; has accepted that Darwinism was multivalent, capable of generating a spectrum of ideological derivatives. Indeed there has been a lively (if sometimes sterile) semantic debate, whether the term ‘Social Darwinism’ should be applied to the gamut of these derivatives, or be delimited to social theory that used concepts supposedly central to Darwinian biology – such as natural selection, or differential reproduction. The generalists, for instance, are more inclined to accept (say) Lamarckism as a legitimate source of ‘Social Darwinism’, given that Darwin continued to use Lamarckian theory, while the restrictionists tend to exclude it. This obviously affects the status given to Lamarckians such as Herbert Spencer, who has traditionally been perceived to be a quintessential ‘Social Darwinist’.

Revisionist historiography in this matter has emphasised continuity rather than discontinuity in intellectual history.