The phrase "affirming the notion" is correct and usable in written English.
It can be used when you want to express support or validation for a particular idea or belief.
Example: "The research findings are affirming the notion that early intervention can significantly improve outcomes for children with developmental delays."
Alternatives: "supporting the idea" or "validating the concept".
Is it another step towards affirming the notion that the military establishment is the sole guardian of the country, not only externally but now internally as well?
On a more millennialist and provocative note, the Singularity also offers a modern-day, quasi-religious answer to the Fountain of Youth by affirming the notion that, yes indeed, humans — or at least something derived from them — can have it all.
Like this site, it was very imperfect but held some good information (like affirming the notion that LGBT orientation is not a choice), and many local leaders didn't even know it existed.
Frances FitzGerald, in her article on Dr. Joel C. Hunter, the senior pastor of Northland church, affirms the notion that "evangelical" and "liberal" are not mutually exclusive terms ("The New Evangelicals," June 30th).
How the idea of fetal rights gained currency is a story of social reaction — to the Roe decision and, more broadly, to a perceived new permissiveness in the 1970s — combined with a determined, sophisticated campaign by the anti-abortion movement to affirm the notion of fetal personhood in law and to degrade Roe's protections.
"Further, it affirms the notion that any differences we see between the mental skills of humans and the other great apes are ones of degree, not kind".
"This rule affirms the notion that contracting with the federal government is a privilege, not an entitlement," said Labor Secretary Tom Perez.
Allen's study would affirm the notion that the Internet does not allow for people to sustain quality relationships with large networks of people, as social networking websites might suggest.
For those who have watched the train wreck that is Roger Goodell's leadership of the NFL over the past few years, the judge affirmed the notion that arrogance coupled with bad judgment are the hallmarks of the Commissioner of the NFL.
