text: **Evaluating approaches to AI**
  No established unifying theory or paradigm has guided AI research for most of its history.[aa] The 
  unprecedented success of statistical machine learning in the 2010s eclipsed all other approaches (so much 
  so that some sources, especially in the business world, use the term "artificial intelligence" to mean 
  "machine learning with neural networks"). This approach is mostly sub-symbolic, soft and narrow. Critics 
  argue that these questions may have to be revisited by future generations of AI researchers. 