False argument demonstrated by Glossop & his minions (7)

I believe the answer is:

sophism

I'm a little stuck... Click here to teach me more about this clue!

'false argument' is the definition.
(I've seen this in another clue)

'by glossop his minions' is the wordplay.
'SOPHISM' is hidden within the letters.
But, I'm uncertain how this is indicated.

'demonstrated' is the link.

Can you help me to learn more?

(Other definitions for sophism that I've seen before include "False argument" , "faulty reasoning" , "specious argument" .)

I've seen this clue in The Hindu.

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