This is not a good time for fans of Anglo-Saxon culture. After Brexit, Donald Trump's electoral victory (however precarious it is) tells us that in the cradles of democracy and parliamentarianism, the visceral reaction has triumphed over the cerebral vote. It is well known that in the mid-19th century the existence of human remains that differed from those of conventional Homo sapiens was discovered in the Neandertal Valley near Düsseldorf, Germany. The Neanderthals were sapiens, but less. Their brains were somewhat smaller and they generally had somewhat ape-like features. They had inhabited Europe, coexisted with the sapiens sapiens, but they had been wiped out by vague causes, perhaps related to their inferior intelligence. Their absence was certainly a relief, but it was later discovered that before disappearing, some Neanderthals had mated with Homo sapiens, which is why so many of us have some Neanderthal genes. One thinks that perhaps this triumph of Anglo-Saxon populism has something to do with a genetic leap backward.

It is certain that in the United States and the United Kingdom, the votes of the triumphant party came from the less educated and urban strata of the population; Trump proclaimed during the campaign that he loved poorly-educated people and Michael Gove, a Tory supporter of Brexit, said shortly before the referendum that people were already tired of the experts. And, in fact, in both countries the brainiest of the press, especially the newspapers, were clearly aligned against populist choices. These thoughtless voters remind us of that saying by Machiavelli, "Men are so simple-minded and so controlled by their immediate needs that he who deceives will always find someone who will let himself be deceived."

This bitter observation of a very disillusioned thinker of the 16th century has been validated once again five centuries later. Because the string of lies that have been released by the populist winners on both sides of the Atlantic have made us think of Goebbels: A lie repeated a thousand times becomes true. Or it turns into post-truth politics. Ask the nationalists all over the world. And these conveniently repeated post-truths (that Obama was not an American, that all Mexicans are rapists and murderers, that commerce harms us, that Europe robs us, that Spain robs us, and a very, very long et cetera), become powerful electoral weapons in the Anglo-Saxon, French, and of course in the Catalan and Basque worlds, where it is so easy to deceive the Neanderthals.

Two questions arise immediately in the face of this alarming situation. First, what is the cause of this electoral backward turn, this regression to Neanderthal voters? And second, there is the question of whether or not this visceral irrationalism is likely to spread to other advanced countries, particularly Europe. The second question has a two-part answer: That there are populist parties in Europe willing to gain power by lying left and right is undeniable. In Greece the group called Syriza has been in power for a year and a half, swallowing one lie after another. This has discredited them there, but in the rest of Europe it does not seem to have affected populist voters. Therefore, and this is the second part, it is quite possible that populism will triumph in countries like France, Holland, and Italy, and parties of this sort are already in power in Poland and Hungary. The situation, therefore, is extremely alarming, which leads us to the first question: What is the reason for the rise of populism? Because the only way to solve a problem is to study its causes.

The populist outburst is attributed to the Great Recession. This is only partly true, because there is no recession that lasts 10 years. Both the United States and the United Kingdom, with very low unemployment rates, left the recession behind long ago, although there were sequels that weighed heavily on the rebellion by voters and favored electoral Neanderthalism. But there is a particular factor that weighs heavily on more than one country, and continues to weigh on the rise of European populism: immigration. Trump's (of course, dishonest) promise to build a wall on the Mexican border was decisive in his victory. Boris Johnson and Nigel Farage's assertion that Brexit would put an end to the entry of foreign workers was equally effective in handing the triumph in Britain to the enemies of the European Union. Similar things advance populism in France, Germany, Holland, Denmark, etc. In Hungary, the government of Viktor Orbán is distinguished by its radical nationalism and its total opposition to immigration. Only in southern Europe is the xenophobic component of populism more diluted, although the demographic pressure in the Mediterranean reaches dreadful dimensions.

Perhaps the most serious problem facing the planet in the 21st century is excessive population growth. This is something that the concerned majority, as Machiavelli said, is hardly conscious of in their immediate reality. Since the start of the Industrial Revolution (at the end of the 18th century) human population has grown out of control. If in the year 1800 there were about 900 million human beings on Earth, in a little over 100 years the number had doubled, and during the 20th century it doubled several times more, so that today the number of humans on Earth is around 7.5 billion. And it continues to grow; although the growth rate has moderated slightly, it is likely that if something drastic is not done to limit growth, by the end of this century we will be at about 10 billion. If the present figures seriously endanger the integrity of the planet, 2.5 billion more inhabitants (the total number of inhabitants in 1950) would create unimaginable tension. We are like people crowded into the cabin of a Marx Brothers movie; more and more people enter, but the space does not increase.

Even worse than the total figures are their geographical distribution. The temperate zones are very full, but their population does not grow. The most alarming fact is that the poor countries, the equatorial countries, Africa and the Middle East, are where the population grows the most. Hence the mass migrations of the millions who are willing to risk their lives leaving their land and upon reaching wealthy countries are willing to work for a wage that is miserable in their new land but would be splendid in the country they left. Hence the hatred of the West by many inhabitants of these countries (the Islamic State, al-Qaida, Boko Haram...) who prefer to return to the Middle Ages rather than accept the superiority of Christian civilization. It is Neanderthalism of underdevelopment. Japan did the opposite and today, with all its problems, it is one of the most developed countries.

The demographic explosion in the Third World is dividing the planet with a deep gap between rich and poor countries. The solution is not to erect walls and wire fences that worsen the division. The solution is to attack the cause of the problem: the overpopulation of the most backward countries. It is the responsibility of the rest of the world to fight for these countries to progress economically and to stabilize demographically. It requires more education (including sex education) and less weaponry, more trade and more jobs. Let us not be myopic like Machiavelli's contemporaries. Let us think globally, because we have only one planet and the destinies of humanity are strongly intertwined. We all travel on the same ship. Let us not try to shut ourselves up in our little castles and ignore the problems of our fellow men. Let us not hide our heads, like the proverbial ostrich. Let's not go back to the Neanderthal Era.