know one's own mind

present singular third person knows one's own mind · participle present knowing one's own mind · past knew one's own mind · participle past known one's own mind · alternative know one's mind · alternative know one's own head

1. idiomaticTo clearly understand one's own feelings, intentions, preferences, etc; to know precisely what one wants; to be decisive or determined.

   He was the strong man who knew his own mind and could not be shaken.

   1920, P. G. Wodehouse, chapter 3, in The Coming of Bill

   5 more examples

   Demi knew his own mind, however, and tranquilly carried out his plans, unmoved by the tongues of the anxious mammas or the jokes of his mates.

   1886, Louisa M[ay] Alcott, chapter 1, in Jo’s Boys, and How They Turned Out. A Sequel to “Little Men.”, Boston, Mass.: Roberts Brothers, →OCLC

   He sadly wants strength of purpose; and, like weak men in general, he only knows his own mind when a resolute friend takes him in hand and guides him.

   1889, Wilkie Collins, chapter 54, in The Legacy of Cain

   "Wise girl—strong-minded girl, knows her own mind," muttered Mr. Churton.

   1892, W. H. Hudson, chapter 18, in Fan: The Story of a Young Girl's Life

   "I'm a conservative Republican who hasn't approved of any conservative Republican in years because most conservative Republicans aren't conservative enough for me." So says John J. Wilson, 72, who knows his own mind and does not hesitate to speak it.

   1973 August 13, “The Law: The Little American”, in Time

   Ronald Reagan knew his own mind. He had firm principles - and, I believe, right ones. He expounded them clearly, he acted upon them decisively.

   2004 June 11, Margaret Thatcher, “Remarks by Former British Prime Minister Margaret Thatcher”, in New York Times, retrieved 26 Dec 2011