People participate in society as individuals for their own sake. People improve on their social competence (this involves all socionics functions, not just Fe and Fi) for themselves, which in turn spills over as a benefit to others as well. That does not mean that a person is doing so with the intention of influencing another's convictions; in such a case that person is acting as an external authority. A person will want to change their convictions closer to reality when it is clarified to them. When a person's philosophy, convictions, principles, values, worldview, life mission, goals, and plans are grounded in objective reality, that person will produce productive results that will also by default have positive consequenses for other people. The end result will vary from person to person according to what their values/convitions are (evaluative relationship with reality, Fi and Fe), on their pain and frustration tolerance (discipline/focus), and on their overal biological energy and intensity (which I think it is at least partly genetic).
When a person is fully grounded in reality (in socionics, my theory is that there would be enough information flowed in each function [facet of reality] that would form rational principles in every aspect of a person's relationship with reality), that person will have no need for external authority, and will socialize on the basis of their incentives.