You’ve likely faced the question: “paper or plastic?” Clearly the paper bag is the better option, right? Or is it? In a TED Talk, Leyla Acaroglu has a challenge for us. She wants us to rethink our environmental folklore, or how we decide what is good or bad for the environment.

We want to do the right thing, but how do we know we’re having a net positive impact? When you account for how materials are extracted, to how they’re used, and to how they’re eventually discarded. As for the paper bag, have you considered where and how the cellulose for the paper comes from, and what happens when it’s discarded?

Over time, decisions like paper vs plastic turn into folklore and many of us go along with it. Leyla’s larger point, I think, is that the “right” answer is probably not all of one thing or another. One solution might be optimal in one scenario, but not in a different scenario with different needs. Basically, avoid gross and rigid generalizations. That goes for designers and consumers.

Watch Leyla’s TED Talk here.