assuming

You're close, but they're not synonyms.

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radical

4 : one that is radical: as a : one that advocates a decided and often
extreme change from existing, usual, or traditional views, habits,
conditions, or methods <a literary radical at heart, he was fighting
... for a reevaluation of values -- R.E.Spiller> <regarded as
something of a radical in anthropological circles ... when he proposed
that Neanderthal man might be classified as Homo sapiens --
R.W.Murray> <the young radicals ... who met regularly to discuss the
new musical theories -- Edward Sackville-West & Desmond Shawe-Taylor>

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