Foundational VirtueA lack of humility tends to diminish other virtues such that humility is viewed as a foundational virtue. For example, if you are generous, being humble about it makes it clear that your intentions are virtuous. Using generosity to promote yourself can be perceived as virtue signaling.
Foundation of KnowledgeHumility may be required to examine one's biases and fallacies such that it is considered a basis for knowledge. For example, a scientist who suffers from arrogance may miss motivated thinking that has colored their analysis of data.
IntrospectionIntrospection is the ability to examine and evaluate your own thoughts and emotions. This requires the humility to see yourself in a realistic light in order to find valuable self-criticisms that can be used to improve.
AltruismAltruism is an act that is motivated by concern and empathy for others. If you promote your good deeds by virtue signaling or if your good deeds boost your pride, altruism may not be your true motivation.
Silent GoalA silent goal is the practice of keeping your goals to yourself based on the idea that this increases your motivation to actually achieve the goal. For example, if you tell everyone you are going to lose weight they many all congratulate you and encourage you. This gives may give you the validation that you were seeking such that you lose your motivation to actually follow through on the goal. Silent goals are characteristic of the humble who don't promote their accomplishments and certainly don't promote things they haven't yet accomplished.
Self-ConfidenceHumility can be a state of high self-confidence whereby an individual isn't worried how they are perceived by others. In other words, the humble may be unconcerned with obtaining validation from others such that they feel no need to promote themselves.
Low Self-PreoccupationHumility can stem from a state of low self-preoccupation whereby you are concerned with greater matters than how you are perceived. For example, a professor who is caught up in research and ideas such that they rarely think about their prestige or position. Such an individual may achieve social status incidentally without ever thinking about it.
ModestyModesty is outward directed and humility is inward directed. Other than that they are essentially the same virtue. Modesty applies to your communications with others. Humility applies to thinking and emotions.
NormsCultural norms that call for displays of humility such as bowing.
Sustained AdvantagesHumility is tested where you have significant social status, talent or accomplishments. The ability to remain humble in the face of such successes is characteristic of people who sustain these advantages over time.
False ModestyFalse modesty is a collection of social behaviors that involve elaborate displays of humility -- often because its expected in a particular situation. For example, an actor in an interview who is told they are amazingly talented may respond with something charmingly modest that is understood as a social technique.
CountersignalingCountersignaling is a social strategy that involves downplaying yourself as a means of signalling social strength. For example, downplaying your wealth as a signal that you're so wealthy you have no need to advertise it.
Self-DeprecationSelf-deprecation is the act of saying negative things about yourself, typically in the context of humor or as a defense against insults. This is a potent form of countersignaling that shouldn't be confused with weakness, low confidence or actual humility. This tends to be a cultural thing. For example, it is a far more common social approach in England than North America.
Strategic HumilityFriedrich Nietzsche thought of humility as a strategy used by the weak to hide their inadequacies. This is part of his theory of the last man -- a culture that condemns strengths and risk taking but glorifies weakness and risk avoidance. Nietzsche tends to go to extremes to provoke thought and this represents a narrow view of humility.
StoicismStoicism is an approach to life that focuses on being virtuous in each moment while being completely neutral to both hardship and good fortune. The stoic philosophers advocate humility such as self-deprecation as a defense against insults. If you insult a stoic, they are only likely to point out their other possible criticisms that you have missed. For example, "I am also short and bald." This clearly communicates that you are too grounded and aware of your own flaws to be hurt by criticism.
Freedom from pride or arrogance.