Why firms are piling into artificial intelligence

SOMETIMES it is perceived as a figment of the far future. But artificial intelligence (AI) is today's great obsession in Silicon Valley. Last year technology companies spent 8.5 billion on deals and investments in artificial intelligence, four times more than in 2010. Nearly all of the world's technology giants, including Google, Microsoft, Facebook, Amazon and Baidu, are competing fiercely to hire the best AI experts, snap up start-ups and pour money into research. The technology has not always been so popular.