[S]elling trade books is essential for subsidizing a core collection of other books, which often cost more to maintain. For a store like Great Expectations, which dealt in academic and scholarly literature, trade books were what allowed the store to stay in business. After all, it’s easier to sell a copy of Oliver Twist than it is to sell obscure books about Martin Heidegger.They should stick to books by him. Books about him can probably make do with their authors making them required texts for their students. I expect a modestly priced paperback of Contributions is just what the industry needs.