Ones have a strong unconscious tendency to compare reality with what should be. They generally have a set of ideal standards against which they measure themselves, the behavior of others, and the world around them.
These ideals differ from person to person. Some Ones could be preoccupied with spiritual standards while others, like advice columnists, focus on good manners. Other Ones might be social reformers while others still are simply intent on living upright lives or excelling at their jobs.
Healthy Ones specialize in accurate moral perception and objective evaluation. More than other Enneagram styles, Ones can be ethically discerning, dispassionate and fair. They can make excellent priests and judges as well as constructive social commentators.
Healthy Ones can be selfless and morally heroic, willing to sacrifice personally for principle. If they have a cause or a mission, they will work hard and responsibly to fulfill it. They value ethics and integrity above expediency, profit or easy solutions. People with this style often display a balanced, cheerful perfectionism that they temper with forgiveness and compassion.
When Ones are less healthy, their preoccupation with principles and high ideals degenerates into a more mundane concern with the rules. Such Ones may still crusade for a cause but have more ego-involvement than they realize. They confuse morality with moralism and discernment with judgment.
A less healthy One might sacrifice to uphold the rules, but unconsciously resent it. Ones can become critical or angry when their reforming zeal isn't shared by the world at large. They might still work hard and hold themselves to strict standards of behavior, but their speech can be punctuated by sharp-tongued remarks, as their anger breaks through. Their calm, ethical perspective can also give way to dualistic thinking * either/or propositions, right/wrong dilemmas that reduce complex situations to simple black and white choices.
A One's attempt to be good is a tense enterprise, often leading to rigid behavior and obsessive worry. Many Ones fight their desires, especially the bad ones. These are often sensual in nature, but, in general, bad impulses are the opposite of whatever the One considers good and virtuous behavior.
Social problems can emerge because Ones have trouble knowing when they are angry and don't realize how scolding or repressive they sound to others. When insecure or feeling criticized, a Ones defensive reaction is to start judging. They simply don't accept reality as it is and don't think you should either.
Whatever Ones disapprove of in their own behavior is what they condemn in others. They may not allow themselves to act badly but that doesn't mean they don't want to. Ones in this state tend to beat down or contain their desires and then project them outward.
So a One might see an inviting place to swim on a summer day and suddenly begin to talk about the evils of laziness and the skimpy bathing suits people wear nowadays. The One reverse-projects his sensual desire to swim onto the environment and then indicts the desire.
Very unhealthy people with this style can grow obsessive, paranoid and zealous. They can be cruel and persecutory in the service of goodness. Unhealthy Ones can be morally vain and hypocritical, as well as obsessed with fulfilling ill-conceived projects and missions. Many forms of religious and ideological fundamentalism are shot through with the spirit of unhealthy Oneness.