Philosophy skeptics have a tendency to sniffingly dismiss the field as useless. “What’s the point?” they ask, shrugging at the greatest ideas in human history. Well, aside from the intellectual pursuit of the truth etc., one point of philosophy is it shapes the world around us: Societal instincts and political ideals are often an expression of theories first put forward in philosophy books.

This isn’t just some ancient tendency but an ongoing, modern phenomenon. Global leaders and grassroots ideologues continue to refer to philosophers as the inspiration behind their political outlook. France’s President Emmanuel Macron spent years working with a philosopher, and even the American white nationalist movement known as the Alt Right has its philosophical heroes.

For those hoping to make sense of politics in 2018, here are a few of the philosophers worth knowing.

France: Paul Ricœur

Macron’s frequent use of the phrase “et en même temps” (“and at the same time”) is a reflection of the influence of Paul Ricœur. The philosopher, recognized as one of the greatest French thinkers of the 20th century, was known for his dialectic outlook. Rather than setting out one strident opinion, Ricœur (who died in 2005) tended to acknowledge two contradictory viewpoints and attempt to reconcile them.

Before Macron became a politician, he spent two years working with Ricœur, and the philosopher’s thinking is apparent in how Macron conducts politics. The French president is strikingly pragmatic, and doesn’t hold tight to any one political ideology. Macron appears perfectly happy to consider ideas from both the right and left—which makes it hard to predict how he’ll react to unfolding events.

China: Confucius

Xi Jinping, the leader of China, is a vocal fan of the ancient philosopher Confucius. As China’s economic and global political clout grows, those hoping to understand Xi’s policies would do well to take a look at the 2,500-year-old Confucian school of philosophy.

Much of Xi’s interest in Confucianism is opportunistic, argues Bryan W. Van Norden, a philosophy professor at Yale-NUS College. “He sometimes cites the Confucian classics the way some cynical US politicians quote the Bible,” writes Van Norden in an email to Quartz. “Because Confucianism is paternalistic, Xi promotes it in order to give the people of China a set of values to believe in that he hopes will encourage obedience.”

Most people in China are no longer beholden to Communist values, says Van Norden, and Xi uses Confucianism to encourage deference. This is a misreading, he notes, as “Confucius stresses governing by persuasion” and always with “the happiness of the common people” as the ultimate goal.

That said, Xi does seem to genuinely share some Confucian ideals. As Van Norden explores in his book, Taking Back Philosophy: A Multicultural Manifesto, Confucius strongly believed in the importance of public officials’ integrity. Xi, in turn, has led an anti-corruption drive.

Still, Van Norden suggests that Xi’s emphatic endorsement of Confucius may not lead to the subservience he desires: “Classics are classics for a reason, and if rulers encourage people to read them, they may not be happy with the heroic ideals they inspire,” he writes. Indeed historically, Confucius scholars have often opposed the government’s orthodoxies.

Russia: Aleksandr Dugin

He may not be a good philosopher, but the man known as “Putin’s Brain” certainly considers himself a philosopher. Dugin draws on a dubious interpretation of Martin Heidegger to argue strongly against acceptance and use of technology.

A big fan of US president Donald Trump, whom he has called “the American Putin,” Dugin also believes there should be several world powers and that Russia should lead the block that once covered the Soviet Union. This Russian territory would advocate for hierarchy, tradition, and strict legal structure across its region, while North America and Europe could get on with the business of liberalism, individual rights, and free markets. Dugin believes Trump’s nationalist policies are well suited to such developments, and considers him a positive opponent to the liberal global elite.

Dugin’s writing is incoherent to the point of being deranged, and the extent of his influence is uncertain. But regardless of whether Russian President Vladimir Putin carefully reads Dugin’s work, the philosopher certainly has a high profile within Russia.

The European Union: Jürgen Habermas

The leaders of the European Union don’t have to read between the philosophical lines: One of the great thinkers of the 20th century is still alive, now aged 88, and writing on the European Union (among other topics).

Jürgen Habermas is a member of the Frankfurt School, a group of influential thinkers whose members include Herbert Marcuse (the intellectual guru of American hippies, recently featured in the Coen Brothers’ Hail Caesar), Walter Benjamin (one of the most influential cultural theorists of all time), and Theodor Adorno and Max Horkheimer (whose joint work The Dialectic of Enlightenment, is the flagship text of the Frankfurt School).

Habermas believes that a properly functioning EU would be a powerful form of democracy at its best. He’s furious at the political elites and institutions (such as the European Council) that he believes are wielding unchecked power. Habermas is a careful critic, who cares deeply about the ideals of the European Union. His work shows just how much we’d lose, should the EU fail.

The Alt Right: Nick Land

The white nationalist group sometimes known as the Alt Right is not an enlightened political movement, but it’s nevertheless influenced by philosophy. Various threads of alt right ideology draw off a 1990s neo-fascist philosophy created by British academic Nick Land and known as Dark Enlightenment.

The philosophy, also popular among some Silicon Valley leaders, has been described as “an acceleration of capitalism to a fascist point,” and its ideas center on technology, warfare, feudalism, corporate power, and racism. Throughout history, fascists have distorted ideas in philosophical works to serve their purpose, and Dark Enlightenment is the latest example of such a phenomenon.

Philosophy has a reputation for staying within its ivory tower, but its ideas inform and shape the views of those who wield power. Philosophers such as Confucius, Ricœur, and Habermas are worth reading simply because they’re fascinating. Today, it’s also worth reading them through the lens of the political philosophies they have inspired.