Some writers even suggest that on these grounds we should be wary about combining the two. I think the choice between reductionist and systemic is more relevant. What you see is what you get. Science may therefore improve its knowledge of reality by an incremental process. The methods of science allow us to reach agreement on the nature of the world, and to have some confidence in our shared perceptions when they are developed through science.
Constructivism takes a different view.
It holds that the world we experience is our own construction. We do not experience the world directly, constructivists say. We filter it through our senses, and through the frameworks and assumptions we use to make sense of it. And some constructivists appear to be making stronger claims than that. Each of us necessarily experiences a different world.