An analysis of the language in social media messages posted via the Internet determined that, on average, the use of words associated with positive moods is common in the morning, decreases gradually to a low point midaftemoon, and then increases sharply throughout the evening. This shows that a person' s mood typically starts out happy in the morning, declines during the day, and improves in the evening. The reasoning in the argument is most vulnerable to criticism on the grounds that the argument overlooks the possibility that ['most of the social media messages posted in the evening are posted by people who rarely post such messages in the morning', 'the number of social media messages posted in the morning is not significantly different from the number posted in the evening', 'the frequency in the use of words in social media is not necessarily indicative of the frequency of the use of those words in other forms of communication', "people's overall moods are lowest at the beginning of the workweek and rise later, peaking on the weekend"]