Knowledge is dynamic. Meaning is constructed. Learning includes constructing representations. Teaching is negotiating construction of meaning. Thinking and perception are inseparable.
Problem solving is central to cognition.
Constructivism is simply the wrong revolution. It's a little too anti-realistic. Constructionism is different from constructivism. In contrast to many personality theorists, I was also impressed by what seemed to me a profound lability in self-conception. We don't seem to have a single, stable conception of ourselves, it seemed to me, but to have the capacity for infinite fluctuation.