Our history abounds with stories of individuals perpetrating the most destructive and harmful acts: killing and torture, bringing misery and untold suffering to large numbers of people. These incidents in human history can be seen as reflecting the darker side of our common human heritage. These events occur only when there is hatred, anger, jealousy, and unbounded greed. World history is a record of the effects of the negative and positive thoughts of human beings. This, I think, is quite clear. By reflecting on these past occurrences, we can see that if we want to have a better and happier future, now is the time to examine the mindset of our present generation and to reflect on the way of life that it may bring about in the future. The pervasive power of these negative attitudes cannot be overstated.

Despite being a monk and a supposed practitioner of the Bodhicaryavatara [“The Way of the Bodhisattva”], I myself still occasionally become irritated and angry and, as a result, use harsh words toward others. Then, a few moments later when the anger has subsided, I feel embarrassed; the negative words are already spoken, and there is truly no way to take them back. Although the words themselves are uttered, and the sound of the voice has ceased to exist, their impact still lives on. Hence, the only thing I can do is to go to the person and apologize, isn’t that right? But in the meantime, one feels quite shy and embarrassed. This shows that even a short instance of anger and irritation creates a great amount of discomfort and disturbance to the agent, not to mention the harm caused to the person who is the target of that anger. So in reality, these negative states of mind obscure our intelligence and judgment and, in this way, cause great damage.

One of the best human qualities is our intelligence, which enables us to judge what is wholesome and what is unwholesome, what is beneficial and what is harmful. Negative thoughts, such as anger and strong attachment, destroy this special human quality; this is indeed very sad. When anger or attachment dominates the mind, a person becomes almost crazed, and I am certain that nobody wishes to be crazy. Under their power we commit all kinds of acts—often having far-reaching and destructive consequences. A person gripped by such states of mind and emotion is like a blind person, who cannot see where he is going. Yet we neglect to challenge these negative thoughts and emotions that lead to near insanity. On the contrary, we often nurture and reinforce them! By doing so we are, in fact, making ourselves prey to their destructive power. When you reflect along these lines, you will realize that our true enemy is not outside ourselves.

Related: Inside Out 

Let me give you another example. When your mind is trained in self-discipline, even if you are surrounded by hostile forces, your peace of mind will hardly be disturbed. On the other hand, your mental peace and calm can easily be disrupted by your own negative thoughts and emotions. So I repeat, the real enemy is within, not outside. Usually we define our enemy as a person, an external agent, whom we believe is causing harm to us or to someone we hold dear. But such an enemy is relative and impermanent. One moment, the person may act as an enemy; at yet another moment, he or she may become your best friend. This is a truth that we often experience in our own lives. But negative thoughts and emotions, the inner enemy, will always remain the enemy. They are your enemy today, they have been your enemy in the past, and they will remain your enemy in the future as long as they reside within your mental continuum. Therefore, Shantideva says that negative thoughts and emotions are the real enemy, and this enemy is within.

This inner enemy is extremely dangerous. The destructive potential of an external enemy is limited compared to that of its inner counterpart. Moreover, it is often possible to create a physical defense against an external enemy. In the past, for example, even though they had limited material resources and technological capabilities, people defended themselves by building fortresses and castles with many tiers and layers of walls. In today’s nuclear age, such defenses as castles and fortresses are obsolete. In a time when every country is a potential target for the nuclear weapons of others, human beings still continue to develop defense systems of greater and greater sophistication. The strategic defense project initiated by the United States, widely known as “Star Wars,” is a typical example of such a defense system. Underlying its development is still the old belief that we can eventually create a system that will provide us with the “ultimate” protection. I do not know if it will ever be possible to create a defense system capable of guaranteeing worldwide protection against all external forces of destruction. However, one thing is certain: as long as those destructive internal enemies are left to themselves, unchallenged, the threat of physical annihilation will always loom over us. In fact, the destructive power of an external enemy ultimately derives from the power of these internal forces. The inner enemy is the trigger that unleashes the destructive power of the external enemy.

Related: The Real Enemy

From The World of Tibetan Buddhism, © 1995 by Tenzin Gyatso, the Fourteenth Dalai Lama; English translation © 1995 by Geshe Thupten Jinpa. Reprinted with permission of Wisdom Publications.