O! more than Gothic ignorance.

Fielding’s exclamation invokes the common Enlightenment-era contrast between “Gothic” (i.e., medieval, feudal, or monkish) darkness and the supposed clarity of modern reason. Read this way, the line is a cry of impatience at a kind of blindness or superstition that the speaker judges even worse than the benightedness stereotypically attributed to the Middle Ages. The force comes from the comparative: it is not merely ignorance, but an ignorance surpassing what polite eighteenth-century discourse imagined as the nadir of intellectual life. Without the surrounding passage, however, it is hard to say whether Fielding is targeting religious bigotry, legal corruption, social prejudice, or personal folly—subjects he often satirizes.