It cannot be denied at an intuitive level that there is a moral law that governs the reality we inhabit. But it is also evident that each individual possesses unique traits that, when cultivated, bring into the world a 'flavor' or manifestation of good that cannot be replicated. No two people are exactly alike, and each possesses the potential to exemplify in original ways those goods that are universal and eternal.
For example, I have four siblings who are each unique examples of goodness, but that goodness manifests itself through their unique characteristics. One is highly creative and observant, another is nurturing and empathetic, a third is assertive and focused, and a fourth is eclectic and confident. Each is a close friend but in very different ways. Each relationship is very good but that goodness manifests itself differently because the individuals involved are very different.
Those differences are positive and healthy because they are grounded in goodness. Despite our unique characteristics, opinions, and even beliefs, we share in common certain convictions of right and wrong that anchor our relationships and prevent those differences from becoming divisive. We strive, albeit imperfectly, to subject our individual talents and tastes to universal and eternal goods such as love, humility, kindness, loyalty, and courage.
I've seen a similar dynamic at work on the best teams I've served on during my time in the military. The most successful are those that are comprised of very different people who use those differences for the good of the team and the mission. There is plenty of 'diversity' but those various personalities coalesce around a single shared purpose. Individuality both contributes to and is subordinate to the good of the team and the mission.
People are at the same time capable of great dignity and "liable to all the selfish bias" that human nature entails. Just as we are capable of manifestations of good that are unique to us as individuals, so we are capable of unique evil. One who could be courageous may choose to be a tyrant. Another who could prove insightful may instead be conniving. A third who could nurture may smother instead. Individuality and diversity are not enough. They must be grounded in goodness to be meaningful in light of our moral reality.
Our capacity for both unique good and evil is the tension from which springs our duty to cultivate the one and deny the other. If everything we chose to do became good just because we felt like it, with no external standard for goodness, then duties would not exist. Who needs to be told to do what they feel like doing? Where are the sacrifice and discipline in surrendering to one's appetites? Children don't need to be told to play but to clean their rooms.
But there is no meaning to be found in simply surrendering to one's appetites and calling that 'individuality.' Such uniqueness is only a cheap imitation of the real, particular good we are each capable of. Consider any heroic story worth telling, regardless of if it's true or fictional. The hero inevitably chooses to sacrifice something for a greater purpose. Were he to simply satisfy one craving after another there would be no story, only a cautionary tale. But stories where the hero disciplines himself to fulfill a worthwhile duty or pursue a higher good inspire us to do so ourselves. We intuitively sense there is something truly meaningful in what he does and, unless our souls are completely calloused over by cynical and nihilistic attitudes, we sense there is a meaningful part for us to play as well.
There is no meaningful individuality apart from what is good. But in pursuit of and service to what is good, we find that there is something uniquely good about ourselves that others need. Accepting and appreciating this foundational truth is the first step in the discovery of enduring meaning.