fun vs seriousness

fun

noun
  • amusement, enjoyment or pleasure 

  • playful, often noisy, activity. 

verb
  • To tease, kid, poke fun at, make fun of. 

adj
  • Enjoyable or amusing. 

  • Whimsical or flamboyant. 

seriousness

noun
  • The state or quality of being serious. 

How often have the words fun and seriousness occurred in a corpus of books? (source: Google Ngram Viewer )