What do you think dickens means by "lived upon the total abstinence principle"? this is from the final stave of a christmas carol

In stave five from "A Christmas Carol," Charles Dickens suggests that Scrooge has become a better man and mentions he "had no further intercourse with Spirits, but lived upon the Total Abstinence Principle." Thus, he means that he decided to keep himself from drinking and never drank alcohol again.

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