Richard Foote, Glasgow, told of a boy he knew whose life had been "largely hell" in primary school because he had been picked on.
At his birth, doctors warned that he would not be able to carry on a normal life or social existence. The boy subsequently went on to special education.
"The man I'm speaking about is my stepson and I have never met anybody more socially inclusive and into the world and able to speak to people," Mr Foote told the conference. "He is extremely confident after going to a special school.
"Social inclusiveness, however, is making this less and less of an option for many of our children in our drive for mainstreaming."