Dear Mr. Hemeier,
As far as I know the term "constructivism"
was introduced in psychology by
Piaget. The modifier "radical" was added by me to cover the
further developments of
constructivism by Heinz von Foerster, Humberto Maturana,
and myself. There is no more reason to copyright the
name than to copyright
"phenomenology" or "rationalism" – they are not brands that
are for sale and people have to think to acquire
them.
By the way, you can hear me talk on May 10th
at Vienna University.
Best wishes,
Ernst von Glasersfeld