On World Philosophy Day, the ideas of groundbreaking thinkers like Immanuel Kant, David Hume, and Martin Heidegger will be shared and celebrated across the globe. But at a time when the focus on writers of European descent in Western universities is being questioned, should we think twice about exalting the ideas of people who were racist and xenophobic? And can you separate a philosopher's identity from their ideas?

Once confined to dusty university libraries and lecture theatres, philosophy has hit the headlines of late: more specifically, the debate surrounding philosophy and race. "They Kant be serious!" exclaimed a recent Daily Mail headline on a story that a group called Decolonise Our Minds at the School of Oriental and African Studies (SOAS) in London was campaigning to include more philosophers of colour in the curriculum. They argued that SOAS and other Western universities favour texts by white, male philosophers, at the expense of Eastern thought (although this is itself a disputed term). Their concerns were mirrored by students at Cambridge University, represented by the student union's women's officer Lola Olufemi, who was pictured on the front page of The Telegraph for suggesting that the English course syllabus should include more writers of colour. This reasoning bleeds into protests against statues of imperialists in public spaces, including the monument to Cecil Rhodes at the University of Cape Town that sparked the #RhodesMustFall campaign.

Such groups have been accused of attempting to replace philosophers and writers simply because they are white with little thought to how these minds have transformed the world for the better. However, a SOAS doctoral student and member of the Decolonising Our Minds group told The Guardian that rather than "exclude European thinkers" they are "trying to desacralise European thinkers, stopping them from being treated as unquestionable."

Neelam Chhara, a third-year politics student at SOAS and the Student Union officer for equality and liberation, highlighted to the newspaper that only two of the 26 of the thinkers on her philosophy course were non-European: Frantz Fanon and Mahatma Gandhi.

Bryan van Norden, professor of philosophy at Vassar College in New York has addressed the core of these debates in his new book, Taking Back Philosophy: A Multicultural Manifesto.

In it, he points to the fact that the philosophical traditions of China, India, Africa and the indigenous people of the Americas have indeed been ignored by the majority of academic institutions in Europe and the English-speaking world. This is not helped by the fact that many philosophers themselves held racist and xenophobic views.

To Professor Van Norden, contemporary Anglo-European philosophy is "indefensibly narrow", he tells IBTimes UK.

Firstly, he says that philosophy outside the West is too often reduced to the zen kōans (succinct statements used to meditate) and aphorisms – such as some of the short sayings of Confucius in a way that is patronising.

"In reality, there is a rich tradition of sophisticated argumentation in other traditions," he explains. "Buddhist philosophers provide sophisticated critiques of the position on the self that René Descartes offers, while Confucian philosophers argue for plausible alternatives to the political atomism characteristic of philosophers after Thomas Hobbes".

However, a "widespread" and "intense" belief among contemporary Anglo-European philosophers that there "simply cannot be any philosophy that is indigenous to these cultures" prevails, he adds.

He gives the example of Immaneul Kant, the 18th century philosopher, whose ideas on epistemology, metaphysics, ethics and cosmology helped to define the world today. But that doesn't mean he's not problematic.

"Immanuel Kant is easily one of the top ten most influential philosopher in the Western tradition, but he dismissed someone's comment by saying, 'this scoundrel was completely black from head to foot, a distinct proof that what he said was stupid.' He even categorised the races hierarchically, stating that 'the race of the whites contains all talents and motives in itself,' and blithely asserted that 'a concept of virtue and morality never entered the heads of the Chinese'."

Chinese philosopher Confucius, or K'ung Fu-tzu
Some argue that Chinese philosopher Confucius should be more appreciated in the West Rischgitz/Getty Images

Fellow 18th century philosopher David Hume, a seminal figure in empiricism and the idea that all knowledge comes from the senses, once wrote: "I am apt to suspect the negroes to be naturally inferior to the whites. There scarcely ever was a civilised nation of that complexion, nor even any individual eminent either in action or speculation." Martin Heidegger, meanwhile, influenced philosophers including Jean-Paul Satre – but was aligned with the Nazis.

It may be tempting to dismiss these attitudes as a product of their time, but it's certainly not the case that racism was universally accepted in the past. For instance, contemporaries of Kant and Hume argued against colonialism and slavery in a 1770 polemic called Histoire philosophique des deux Indes [The Philosophical History of the Two Indies].

"Western philosophers did recognise other philosophical traditions until psuedo-scientific notions of white racial superiority became predominant starting in the late 18th century," explains Professor van Norden.

The question remains: is there still value in the ideas of these great thinkers, even if they regarded other people as inferior?

Kwame Anthony Appiah, professor of philosophy and law at New York University, whose course on global ethics includes European, Arab, Chinese and Indian thinkers, told The Guardian that it is important to consider the value of the ideas of philosophers, rather than to promote diversity as a goal in itself.

"Whomever is taught, whoever's work is drawn on, it must always be dealt with critically. That is one of the first principles of a university education," he said.

The fundamental issue is that by ignoring the philosophy of other cultures, academics and thinkers on both sides are losing out.

Professor van Norden stresses that he doesn't want to suggest that the Western philosophy is "bad" and non-Western philosophy is "good" but that philosophy as a whole "can do its task best if it not only becomes multicultural but also returns to its roots in thinkers like Confucius and Socrates who did philosophy that addressed the concerns of everyday life".

"Racism and ethnocentrism are problems in every tradition," he says, adding: "But we can and should try to be better than that."

Taking Back Philosophy: A Multicultural Manifesto will be published in December 2017.