ˈɑː.ɡjuː ˈɑɹ.ɡju kɔːz kɔz kən.ˈkluːd ˈɪntəlɛkt əˈkeɪʒən ˈɹiːzən ˈɹiːzən ʌndəˈstandɪŋ ˌʌndɚˈstændɪŋ think logically The children must learn to reason decide by reasoning; draw or come to a conclusion We reasoned that it was cheaper to rent than to buy a house present reasons and arguments the capacity for rational thought or inference or discrimination we are told that man is endowed with reason and capable of distinguishing good from evil a fact that logically justifies some premise or conclusion there is reason to believe he is lying an explanation of the cause of some phenomenon the reason a steady state was never reached was that the back pressure built up too slowly a justification for something existing or happening he had no cause to complain they had good reason to rejoice a rational motive for a belief or action the reason that war was declared the grounds for their declaration the state of having good sense and sound judgment his rationality may have been impaired he had to rely less on reason than on rousing their emotions