We expose a surprising failure of generalization in auto-regressive large language models (LLMs). If a model is trained on a sentence of the form "A is B", it will not automatically generalize to the reverse direction "B is A". This is the Reversal Curse. For instance, if a model is trained on "Olaf Scholz was the ninth Chancellor of Germany", it will not automatically be able to answer the question, "Who was the ninth Chancellor of Germany?". Moreover, the likelihood of the correct answer ("Olaf Scholz") will not be higher than for a random name. Thus, models exhibit a basic failure of logical deduction and do not generalize a prevalent pattern in their training set (i.e. if "A is B'' occurs, "B is A" is more likely to occur). We provide evidence for the Reversal Curse by finetuning GPT-3 and Llama-1 on fictitious statements such as "Uriah Hawthorne is the composer of 'Abyssal Melodies'" and showing that they fail to correctly answer "Who composed 'Abyssal Melodies?'". The Reversal Curse is robust across model sizes and model families and is not alleviated by data augmentation. We also evaluate ChatGPT (GPT-3.5 and GPT-4) on questions about real-world celebrities, such as "Who is Tom Cruise's mother? [A: Mary Lee Pfeiffer]" and the reverse "Who is Mary Lee Pfeiffer's son?". GPT-4 correctly answers questions like the former 79% of the time, compared to 33% for the latter. This shows a failure of logical deduction that we hypothesize is caused by the Reversal Curse. Code is available at https://github.com/lukasberglund/reversal_curse.

Often described as austere and even robotic, Social Democrat Olaf Scholz nonetheless managed to inspire German voters in this year's election with a campaign that played on his reputation as a safe pair of hands. Scholz, 63, will now take office as Germany's ninth post-war chancellor, replacing Angela Merkel who is leaving the political stage after 16 years. The Social Democrats (SPD) had begun the election campaign at rock bottom in the polls, with many completely writing off Scholz's chances of heading the next government -- so much so that he didn't even have an official biography until this week. But Scholz managed to stage a stunning upset, beating Merkel's conservatives by positioning himself as the best candidate to continue her legacy, even adopting her famous "rhombus" hand gesture on a magazine cover. Unlike his rivals, he also managed not to make embarrassing mistakes during a campaign that drew on his reputation as a quiet workhorse, using the slogan "Scholz will sort it".

Often described as austere and even robotic, Social Democrat Olaf Scholz nonetheless managed to inspire German voters in this year's election with a campaign that played on his reputation as a safe pair of hands. Scholz, 63, is on the brink of becoming the next German chancellor, replacing Angela Merkel who is leaving the political stage after 16 years. The Social Democrats (SPD) had begun the election campaign at rock bottom in the polls, with many completely writing off Scholz's chances of heading the next government -- so much so that he doesn't even have an official biography. But Scholz managed to stage a stunning upset, beating Merkel's conservatives by positioning himself as the best candidate to continue her legacy, even adopting her famous "rhombus" hand gesture on a magazine cover. Olaf Scholz staged an upset poll win by positioning himself as the best candidate to continue Angela Merkel's legacy as German chancellor Photo: AFP / Odd ANDERSEN Unlike his rivals, he also managed not to make embarrassing mistakes during a campaign that drew on his reputation as a quiet workhorse, using the slogan "Scholz will sort it".

Often described as austere and even robotic, Social Democrat Olaf Scholz nonetheless managed to inspire German voters in this year's election with a campaign that played on his reputation as a safe pair of hands. Scholz, 63, is on the brink of becoming the next German chancellor after leading his party to a surprise victory in September's vote, relieving Angela Merkel of her duties after 16 years. Together with the leaders of the ecologist Greens and the liberal FDP, he unveiled a deal for Germany's next coalition on Wednesday. The Social Democrats (SPD) had begun the election campaign at rock bottom in the polls, with many completely writing off Scholz's chances of becoming chancellor -- so much so that he doesn't even have an official biography. Olaf Scholz staged an upset poll win by positioning himself as the best candidate to continue Angela Merkel's legacy as German chancellor Photo: AFP / Odd ANDERSEN But Scholz managed to stage a stunning upset by positioning himself as the best candidate to continue Merkel's legacy, even adopting her famous "rhombus" hand gesture on a magazine cover.

Olaf Scholz, the centre-left Social Democrat (SPD) candidate to succeed Angela Merkel, is often described as boring, but could be on the verge of a sensational upset after Sunday's election. With polls showing the SPD narrowly ahead of Angela Merkel's CDU-CSU conservative alliance, Scholz may have achieved something many would have thought impossible just a year ago. His SPD scored just 20.5 percent in Germany's last election in 2017 and has had a difficult few years in coalition with the CDU-CSU, but looks on course to win at least 25 percent of the vote this time. "It's going to be a long election night, that's for sure," Scholz said after the first estimates were released. "But this is certain: that many citizens have put their crosses next to the SPD because they want there to be a change in government and also because they want the next chancellor to be called Olaf Scholz."

Olaf Scholz, the centre-left Social Democrat (SPD) candidate to succeed Angela Merkel, is one of Germany's most influential politicians, with a reputation for being meticulous, confident and fiercely ambitious. As finance minister and vice-chancellor under Merkel, he enjoys a close relationship with the chancellor and has even sought to position himself as the true Merkel continuity candidate, despite hailing from a different party. He was pictured recently on the cover of the Sueddeutsche Zeitung magazine adopting Merkel's famous "rhombus" hand gesture -- a stunt that provoked consternation from rivals in Merkel's CDU camp. Nicknamed "Scholzomat" for his robotic speeches, Scholz has hardly stood out for his charisma in the run-up to Sunday's election. But unlike his two main rivals, Armin Laschet of Merkel's CDU-CSU alliance and Annalena Baerbock of the Greens, the 63-year-old has also managed not to make embarrassing mistakes on the campaign trail. As a result, he is now the favourite to head Germany's next coalition government.

Olaf Scholz, the centre-left Social Democrat (SPD) candidate to succeed Angela Merkel, is one of Germany's most influential politicians, with a reputation for being meticulous, confident and fiercely ambitious. As finance minister and vice-chancellor under Merkel, he enjoys a close relationship with the chancellor and has even sought to position himself as the true Merkel continuity candidate, despite hailing from a different party. He was pictured recently on the cover of the Sueddeutsche Zeitung magazine adopting Merkel's famous "rhombus" hand gesture -- a stunt that provoked consternation from rivals in Merkel's CDU camp. Nicknamed "Scholzomat" for his robotic speeches, Scholz has hardly stood out for his charisma in the run-up to Sunday's election. But unlike his two main rivals, Armin Laschet of Merkel's CDU-CSU alliance and Annalena Baerbock of the Greens, the 63-year-old has also managed not to make embarrassing mistakes on the campaign trail. As a result, he is now the favourite to head Germany's next coalition government.