Niedenthal et al's classification of smiles erroneously conflates psychological mechanisms and adaptive functions. This confusion weakens the rationale behind the types of smiles they chose to individuate, and it obfuscates the distinction between the communicative versus denotative nature of smiles and the role of perceived-gaze direction in emotion recognition.

Jane is calmly strolling through the forest one lovely day. Suddenly, a large spider drops in front of her face. She immediately freezes; her heart races; her hands tremble; her face broadcasts “fear.” She screams and runs away. Both before and after, she concedes that spiders in this forest are harmless.Jane's reaction to the spider contrasts greatly with the way she normally reacts to events. Normally, or so the story goes, Jane weighs her options thoughtfully, choosing a course of action (...) consistent with her beliefs and with the greatest benefit. Indeed, her reaction to the spider contrasts so greatly with calm, rational, deliberate, belief-consistent action that traditional folk psychology supposed two different kinds of mechanism are at work: animal-like emotion versus human reason. Her emotion explains her reaction to the spider. Her emotion made her do it. (shrink)