

"Self-discipline begins with the mastery of your thoughts. If you don't control what you think, you can't control what you do. Simply, self-discipline enables you to think first and act afterwards." Napoleon Hill
A disciplined mind is a sound mind and vice versa. The mind is disciplined because it has been subjected to sound principles and judgement over a period of time and so thinks differently from many others. Regarding issues of common concern and interest, many people, between 85 and over 95% tilt towards one point of view and the remainder 15% and less are often hounded. True, in a voting situation, numbers matter but realistically, high number doesn't mean logical or rational. This is a talk for another day.
Sometimes people may differ with you on a matter; you may not engage in an argument with them to prove a point and you just may choose to walk away. Again, they may come to terms with your viewpoint months or even a couple of years after. My interpretation is that you were X number of months or years ahead of them. Great minds like Einstein, Columbus, Edison, Ford, and more were way ahead of their time and that's why they made the kind of impact they made.
A disciplined mind essentially exhibits the following traits:
A Disciplined Mind is Rational
A disciplined mind is a rational mind, does things based on reason as opposed to emotions and views issues from an unbiased point of view. A newly elected Governor in a state in the North West Region of Nigeria stated that his government cannot continue the government culture of sharing essential items like milk, rice, etc to adherents during the Yearly Fasting Period that government should be neutral in religious affairs. Shocking as this may seem to some, it's the bitter truth devoid of emotional bias and a very realistic approach to problem solving. Such a mind has been subjected to much disciplined processes to be able to decisively take such a position.
But funny that sometimes the realism of great minds is not often seen and their biases are not shared because they hold views that are dubbed "separatists." Caution is advised here. Many are blind to their often visionary views but these views are so rational and real to them (great minds) that they maintain their grounds against all odds. The great mind is so rational he speaks against the vices of the day. He sacrifices for the benefit of the whole and plain practical in approach to all things, not paying lip service. Truth is you can't process to be a rational mind and not act it.
Is Empathetic with Others
A disciplined mind shows empathy for others. He/She understands other people's feelings, experiences and situations. Reason is simple: they're compassionate having probably either experienced same or by virtue of the conditions they've subjected their minds to, they understand what they're going through.
Now, your empathy towards a person or their cause may not permit to do beyond mere expressions of understanding their plight. Yes, you may not be able to physically do anything. For example, a relative that's accused of an offence that's glaring to everyone that they committed with evidence pointing towards incarceration. The only thing an empathetic mind can say to do in such circumstance is to empathise with the accused and not seek to either influence or erode justice. You cannot be so touched by his crime till you want to do everything to influence the judgement of the courts to set him free. To do that means you have no concern or consideration for the family of the victim. Remember the celebrated South African murder case of the athlete convicted for slaying his girlfriend? The guy's family from all indications, does not consider the other party.
A disciplined mind is not warped in judgement.
A Disciplined Mind is Not Tribal
This is one big problem with my country men today. If one person from one region is accused of corrupt enrichment and abuse of office, his/her kinsmen rise in defence of him/her. They attack anyone who speaks dispassionately about it and in defence of the law. They defend the accused even when it's obvious that he/she is guilty. Meanwhile, they would rise up in arms against a fellow from another who may have committed a less offence.
A disciplined mind is detribalised. The least you can do if you would not openly condemn any negative or shameful act against proprietary standards is to quietly distance yourself from such an act. Eyes are watching and time and posterity is the judge of such matters.
Makes Informed Decisions
A disciplined mind makes informed decisions. Essentially, they're not hasty in making statements. They're great listeners and exercise restraint in every way especially in words because they know that words, once dropped, cannot be retrieved or taken back.
Advised by this background knowledge, they are guided in their decision making. Oftentimes they are accused by the hasty of being slow but based on a combination of skills: listening, calmness, and the exercise of restraint, they make sound and informed decisions or contribution on any issue. It's a mark of true leadership.
Is a Critical Thinking Mind
Critical Thinking is one skill of the 21st Century that not many are aware of, let alone practise. It is a higher order thinking that requires the development of basic intellectual skills, abilities and heights for the benefit of others. Thus, it is selfless thinking. A critical thinker looks at every issue critically: interprets, analyzes, evaluates, draws inferences, seeks to explain and watches for self-regulation in any issue or circumstance. He/She bows to a superior argument. That mind is logical.
Have you noticed that oftentimes 90% of passengers on a bus in Lagos take sides with their usually reckless drivers against other road users? It's the usual trend of things. They often blindly defend the driver regardless of whether he's right or wrong. It's responding on the spur of the moment without first critically x-raying the situation. Of course, a practised mind would respond differently from the often biased majority.
These are the biases and strengths of a practised, disciplined and developed mind. It's the preserve of leadership and to make impact in whatever position your find yourself, it is important for you to get yourself into the corner of self-development where you can train your mind to act rationally, dispassionately, critically and everything that plays in the realm of placing you above the average mind.
Do you have other ideas to add to this list?