Websters 1828 dictionary defines Self-Control as "restraint exercised over one's own impulses, emotions, or desires..."
Let's look at Reuben and Joseph, two of
Joseph was discerning and wise, he had self-control. He was stable and fled temptations. Whereas Reuben was called “unstable as water” (gen.49:4a). Joseph excelled greatly and Reuben did not, one had self-control and stableness and the other didn’t.
Notice thought they are called the fruits of the Spirit. Only when the Holy Spirit is working through us can we produce theses fruits.
To bear the Fruits of the Spirit the Holy Spirit must dwell in us and this is the foundation of self-control.