arbitrary vs unreasonable

arbitrary

adj
  • Determined by impulse rather than reason; heavy-handed. 

  • Not representative or symbolic; not iconic. 

  • Determined by independent arbiter. 

  • Based on individual discretion or judgment; not based on any objective distinction, perhaps even made at random. 

  • Any, out of all that are possible. 

noun
  • Anything arbitrary, such as an arithmetical value or a fee. 

unreasonable

adj
  • Without the ability to reason; unreasoning. 

  • Not reasonable; going beyond what could be expected or asked for. 

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