Back in the day, the educated citizen had access to much less information than we do today. Yet one must imagine a scholarly type would read and reread the same texts, analyzing them in depth, thinking in long form and essentially becoming an expert on the material. They could pull quotes at a moments notice! Today, I just post quotes to my Tumblr so I can Google them later.
Instead of bookmarking countless articles, try going over your Instapaper archives and see what wisdom you find there. Maybe even read a real book.