Type 1(Instinctive Triad)
Ones idealize a moral purity that both transcends reality and is the foundation of it. They see the world through their perceptual filter of how things could be improved, the ideal as opposed to the real, which leads to a constant dissatisfaction with reality. They are eternally frustrated with all the flaws around them and with their eye for improvement feel it is their mission to fix them. They take pride in not wavering in their convictions no matter how unpopular and in resolutely pointing out the right way everybody ought to abide by. When everyone adheres to the same rules/ideals/principles there is fairness and order...and when people break the rules ones truly resent that. "You can't do that because if everyone did what you did..." is a common type one stream of consciousness.
Ones have the strongest inner critic of all types and justify their moral authority to "point out the right way" by constantly putting more effort into being good or virtuous than others. Due to their strict superego there is no type that feels as guilty for being "bad" and harder on themselves to be perfectly good. They are not just conscientious disciplined competent and reliable people who hold themselves accountable to do what they are supposed to do. They go further in the self-control department by continually repressing their "dirty" desires and restricting their indulgences. The more self-control they consistently maintain the more upright they are and the more they've earned both their right to point out how things should be and their duty to hold their enviornment as well as themselves to ideals.
Ones being perfectionists tend to be uptight and anal-retentive about things and aren't the easiest people to get along with. They practice what they preach however which many find sincere and refreshing in an image-dominated society filled with hypocrisy. They continually hold themselves to their own high standards. They do their duty and are dedicated to standing up for what's right through thick and thin as those are extensions of their perseverance. They are also the least likely type to be full of themselves, so much so one gets the sense that they couldn't promote themselves even if they tried.
Anger in particular is an emotion ones have problems with. Ones pride themselves in being stoic and see emotional expression especially spontaneous outbursts as a lack of self-control, but being in the instinctive triad their dominant emotion is anger. Thus a one's relationship to their anger is like a self-imposed noose around their personal volcano that wants to erupt at the slightest thing that they see is wrong around them. The result is a seeping out of resentment agitation and overcriticalness unbeknownst to the one that others find very palpable.
In enneagram theory type ones are (instinctive/gut)-(valuing/feeling/image)-(thinking/head) in that order. Due to their primary instinctive center ones focus on living out their convictions and neglect to use their tiertary thinking center when it calculates an exception to the rules. That's when they turn their thinking center over to their superego to resolve the conflict. Turning themselves over to their superego also causes them to irrationally overvalue self-control which makes them take pride in repressing their "dirty" desires and restricting their indulgences. Ones think they are more rational than they really are due to their stoic nature. Much distortion springs from their overvaluing self-control. This is the root of a one's contractive temperment.
In the lower to average levels of health ones have unrealistic notions of moral purity and self-control that are unattainable. This leads them to having secret indulgences such that their uprightness seems more than it is. Ones seeing their own hypocrisy makes them redouble their efforts only to fail again. As ones get healthier there is more consistency between what they practice and what they preach because their unrealistic moral standards have paradoxically loosened. They realize breaking some rules are okay and it's okay to cut loose a bit. Philosophically speaking the growth path for ones involves eschewing their moral purism in favor of some type of moral humanism.
1w9s see allowing unnecessary self-interested emotions as detracting from their objectivity. They have a greater focus on abstract and impersonal ideals that can withstand the test of time and endure an imperfect world just as they themselves consistently "withstand" and "endure". They are more stoic and cerebral and may theorize about how things should inherently be, the "perfect" virtues to adhere to, the "perfect" way to live by. It's no accident that many philosophers are 1w9s as constructing systems of thought based on their "moral postulates" is textbook 1w9 thinking, starting with assumptions they "just know"(instinctive) to be right(valuing/feeling) to build systems of thought(thinking). The principal author of the Declaration of Independence, Thomas Jefferson, was also a 1w9. The downside of their stronger thinking function compared to their two-winged siblings is experiencing more internal conflicts between what they "reason out"(thinking) and what they "just know to be true"(instinctive). This causes their superego to step in more and lead to a more repressed personality that makes them harder on themselves than others. Spock is a fictional 1w9 and Vulcan history is also very 1w9: "By the 4th century, Vulcan was tearing itself apart. Their rampant emotions combined with a hostile warrior culture led to many wars using atomic weapons. But out of this came a philosopher named Surak, who would propose leading a life governed by logic rather than emotion. His teachings quickly spread, and Vulcan finally began a shift towards peace."
1w2s in contrast sees the 1w9 focus as too detached from humanity and have a more practical morality focus, for example things between people like ethics and etiquette. The 1w2's focus on where to fix things is more in the trenches due to their 2 wing. They value connections between others above abstract ideals in terms of application of principles. They are more "human" which makes them better suited towards activism than philosophy. They take social issues more seriously and define fairness and what is right less in absolute terms and more what they see is equitable for others. This is why they are said to be natural advocates. In comparison to the 1w9, the 1w2 has less internal conflict between thought and action and feels more compelled than burdened. 1w2s feel more compelled to address what needs fixing in the shared interpersonal space between them and others. They see this as their duty. This combined with using the moral highground to establish and protect personal boundaries between themselves and others makes them seem more authoritarian. While they are harder on others around them and can seem condescending, they are also very hard on themselves. They would have a hard time looking at themselves in the mirror if they didn't take action.
1 vs 2: Ones are much harder on themselves than twos. Twos can think highly of themselves merely by seeing themselves as considerate of others. Even when twos are self-critical, they have more of a pride in being self-critical. Twos being image-center first won't hesitate to have outbursts of emotion, which seems like a lack of self-control to the one.
1 vs 3: Ones couldn't promote themselves to save their lives while that's the three's gift should they choose to use it. Threes also have much stronger egos and are sometimes willing to cut corners. In the off-chance ones do self-promote it's for the greater good than personal benefit.
1 vs 4: A one's strict superego precludes them from emotional displays and indulging like a four. Ones unlike fours aren't reactive, they have to look before they leap before reacting emotionally. A four sees being emotional as authentic while a one sees that as a lack of self-control.
1 vs 5: Fives unlike ones don't need to adhere to standards that apply to everyone to think they are good enough. Unlike fives the way ones are rational is tied to self-control. Ones find it easy to engage the world while fives find it draining. Fives don't need to obey the rules while ones are complient to the rules.
1 vs 6: Ones unlike sixes do not worry and are very sure of themselves. They know what their purpose is in the world. They "just know" way things should be and they pride themselves in not wavering in their convictions. Ones have a drive for self-improvement that sixes don't have.
1 vs 7: Ones are inhibited. Sevens are anything but. Sevens do not believe in restricting themselves.
1 vs 8: Ones are contractive while eights are expansive. Eights are very comfortable making exceptions to the rules when judging people. Eights also find it easy to exempt themselves from following any rules. Unlike eights, ones need to follow their rules to consider themselves moral people.
1 vs 9: Ones are tight while nines are easygoing. If the one's dedication to their cause is strong enough they will view losing connection with people outside their family as necessary sacrifices for the greater good while for a nine there is nothing worse than estrangement.