On Sunday 11 April, the first round of the presidential elections in Peru produced a major surprise: the victory, against all the odds, of Pedro Castillo, the leader of the 2017 teachers' strike. In the second round, he will face the reactionary, right-wing candidate of Fuerza Popular, Keiko Fujimori, in a clear expression of enormous political polarisation in a country ravaged by the economic crisis and the COVID-19 pandemic.

Last Saturday, hundreds of activists from across the world met online for the philosophy day school – hosted by Socialist Appeal, the Marxist tendency in Britain – to discuss the revolutionary ideas of Marxism: the only ideas that can help us to understand the world – in order to change it.