The current Portuguese best-selling book is not a whodunit or film star biography but an economic tract. Porque devemos sair do Euro (Why we should leave the euro) by the economist João Ferreira do Amaral (Lua de Papel, €12.60) sets out to prove in 128 pages that the only way forward for the country is to leave the eurozone as quickly as possible.

Already in its fourth printing since it came out in April, the book has generated a buzz and is in the list of top 10 bestsellers – the Wall Street Journal observed that some weeks it is even on a par with Fifty Shades of Grey. According to the author, "it is clear to people that, as it stands, the government's austerity policy is not working. They want to look at all the other alternatives".

Indeed, the Portuguese cannot see the benefits of the drastic deficit-reducing measures the government has inflicted on them in the past months. In 2013 growth will be negative for the third year running. The deficit is taking longer than expected to fall and unemployment remains dramatically high, with 17.5% of the population unemployed.

But will a return to the escudo really be the solution? A longstanding Eurosceptic, Ferreira do Amaral claims that he is not pandering to nostalgia for a symbol of the past. "There is no other way for us to be competitive again," he insists. "I'm not against the euro as such, but the currency is too strong for our Portuguese industry."

The government has refused any possibility of a "Pexit" (Portugal leaving the euro). But meanwhile Ferreira do Amaral is the star guest in all the TV debates on the subject: "Now a taboo is broken."

This article appeared in Guardian Weekly, which incorporates material from Le Monde