The Q&A panellists launched into an emotive discussion around freedom of speech, largely powered by the absence of controversial anti-Islamic activist Ayaan Hirsi Ali who was due to appear as a member of Monday night's panel.

While the exact "security concerns", among other reasons, that led to Ms Hirsi Ali's cancelled Australian tour remain unconfirmed, Federal Environment and Energy Minister Josh Frydenberg blamed it on the need to reform Section 18C to "protect and promote freedom of speech".

"It is very regrettable people have sought to prevent her coming to Australia because they see her as the enemy of tolerance. I see her as an enemy of intolerance," Mr Frydenberg said.

Read the complete original version of this item...