The phrase "controversial notion" is correct and usable in written English.
You can use it to refer to a thought or relevant subject that has generated significant debate or strong disagreement. For example, "Many people disagree with the controversial notion that raising taxes is the only way to generate revenue."
This is a more controversial notion than it may appear.
There would also be the controversial notion that the chef not be shackled to the stove.
An ill-defined, controversial notion is no basis for coherent policy.In this section What are brands for?
The idea that there is an "Israel lobby," with its undertones of dual loyalty, is a controversial notion.
The Senate bill contains no provision for a government-run insurer, which angers leftists; some want to revive this controversial notion.
And governments have left the largest financial institutions intact, leaving the controversial notion of "too big to fail," and the systemic risk that it brings, alive and well.
The consensus, in the end, was that there was no point in muddying a nice, clean referendum with a lot of controversial notions of governance.
The codes of conduct created by ethical consumerist movements to ensure that production practices remain true to certain values themselves embody controversial notions of political representation.
Perhaps Barrie was dabbling in the controversial notions of Darwin and Nietzsche; yet, as Theresa Heskins's spirited revival suggests, it was more likely to be an excuse for an awfully big adventure.
Perhaps more intriguing, Houghton and Wang's results lend credence to the controversial new notion that cancer may arise from stem cells (Science, 5 September 2003, p. 1308 ), although some stem cell experts say they aren't convinced that the bone marrow cells are behaving as proposed by the UMass, Worcester, team.
While Buchanan's characterization of this division is controversial, the notion of a "divided America" is not.
