"Convincingly" is a word in ENGLISH

convincingly ENGLISH
Definition:

in a convincing manner; in a manner to compel
assent.

Few words of positivity

The values we rightly associate with the modern age - the "liberty, equality, and fraternity" of the French revolution - are all endangered today not by the dead hand of tradition but by modernity itself, and they can be salvaged only by moving beyond it.

Harvey Cox, Religion in the Secular City: Toward a Postmodern Theology

WORD SUGGESTIONS
Laugh your heart out.

Manager: Twenty teams in the league and you lot finish bottom ?Captain: Well, it could have been worse.Manager: How ?Captain: There could have been more teams in the league !

cogently ENGLISH

In a cogent manner; forcibly; convincingly; conclusively.

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In a manner fitted to demonstrate; clearly; convincingly; forcibly.

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inconvincibly ENGLISH

In a manner not admitting of being convinced.

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