(I don't have an economics background; apologies if my terminology is confusing.)
It seems like there is often a situation where a firm can take actions to create demand that did not already exist. For example, the classic door-to-door encyclopedia salesman. Before a visit from the salesman, you feel no desire to own an encyclopedia. But the salesman points out that encyclopedias are helpful for a child's development; you look at your child, whom you love, and now you feel a desire to buy an encyclopedia.
I'm interested in economic models of this dynamic, and would appreciate being referred to any.