reasonableness       
noun [ U ] uk/ˈriː.zən.ə.bəl.nəs/ us/ˈriː.zən.ə.bəl.nəs/
 合情合理;公平讲理
the fact of being based on or using good judgment and therefore being fair and practical
  The court will determine the reasonableness of the police activity. 法院将判断警察行动的合理性。 
 There was a sweet reasonableness in her voice. 她的声音里有一种甜美的理性。 
 See: reasonable
 - More examples
 - Beneath his apparent reasonableness toward them, there was an angry intolerance.
 - The insurers retain the right to question the reasonableness of any individual medical expense.
 - They must assess the reasonableness of an employer sacking a worker for sending an email which is critical of a manager.