For evolutionary scientists there is no such thing as "Darwinism". Instead we have a scientific theory that, in combination with Mendel's work, provides the modern or neo-Darwinian synthesis, which explains the development of life on Earth. Although this is a rather succinct definition it effectively sets the limits of the usefulness of Darwin's theory. However, in the last 150 years, there have been many attempts to take Darwin's idea and apply it outside of the context for which it was developed, hence the influence of social "Darwinism" on concepts such as eugenics and a more recent Darwinian nihilism that absolves the individual of any moral or social responsibility.

There is an inherent danger in extrapolating science beyond the realm for which it was intended, but ironically this human trait is perhaps best understood as an evolutionary hangover from the development of our massively expanded brainpower. We have an innate need to expand and develop ideas in order to explain our wider existence or justify our behaviours.

This inherent danger of using Darwin's theory outside of its biological context has lead to attempts to portray Darwin as the de facto cause of 20th century genocide: see, for example, Andre Pichot's book The Pure Society. There is a fallacy at the core of this line of thinking – can scientists really be held responsible for what is done with their ideas when they are misunderstood and corrupted by groups such as the Nazis? I would argue that they cannot: the actions of criminals do not need such highbrow justification and trying to do so merely lends a pseudo-scientific veneer the actions of the Third Reich.

A newer and perhaps more insidious attempt to blame "Darwinism" for human atrocity comes in the form of Dennis Sewell's book The Political Gene: How Darwin's Ideas Changed Politics. Sewell cites Darwin's work as the reason for the development of something that he broadly categorises as a form of moral detachment from societal rules and norms: evolution is random and without purpose therefore I can do whatever I please. He argues that this moral vacuum can lead to disturbed teenagers perpetrating horrific crimes such as the Columbine school massacre. Sewell does not propose that Darwin's theory leads inevitably to such actions, however he suggests that some of Darwin's other writings were racist and not in keeping with modern views. This is hardly a stunning revelation: Darwin was a man of his time and of his society. Sewell is making a common mistake in grafting the faults and flaws of Darwin the man onto Darwinian evolution. Darwin the man has been venerated and condemned during the 2009 celebrations – surely it is now time to move on from either hero worship or iconoclasm to a more nuanced view, just as evolutionary biology has developed since 1859.

An interesting parallel can be seen in how Islamists subvert the essentially peaceful message of Islam into a justification for violence and vitriolic hate. One can no more blame the actions of misguided Islamists on Muhammad than the Nazis or high school shooters can be blamed on Darwin.

Humans have a tremendous capacity for selflessness and creativity but we also have an equally developed ability to cause destruction and misery. Both extremes are a result of our evolutionary heritage. If we blame Darwin for the dark side of human nature, logically we must also credit him with all that is good.