Really? I'm going to agree that your "consuming content" fits this bill (in all mediums mind you. Mindlessly doing anything fits this bill), but I've taken to reading used books with red pen, and scarring the pages with excerpts, thoughts, counterpoints, interpretations, etc. I view that as an absolutely critical part of reading now.
"and it may sometimes happen that he could have found it [some great truth] all ready to hand in a book and spared himself the trouble." -S
You don't FIND these truths in books. The books bring out and expose the truths that lie in your experience. Take, for example, reading the classics in high school (Heart of Darkness, Gatsby, Crime and Punishment, etc). Those books meant notheng to me. My experiential quorum was unmet. I couldn't even vote on whether these topics were relevant (let alone true). It was only after I experienced, felt, lived. Only after being could the books show themselves. The authors feel the same way you feel, they just put it better. More succinctly. We all have the ingredients, they just know how to simmer things.
Compare Schopenhauer with Hemingway (Death in the Afternoon)
"People in a novel, not skillfully constructed characters, must be projected from the writer’s assimilated experience, from his knowledge, from his head, from his heart and from all there is of him. If he ever has luck as well as seriousness and gets them out entire they will have more than one dimension and they will last a long time. A good writer should know as near everything as possible. Naturally he will not. A great enough writer seems to be born with knowledge. But he really is not; he has only been born with the ability to learn in a quicker ratio to the passage of time than other men and without conscious application, and with an intelligence to accept or reject what is already presented as knowledge. There are some things which cannot be learned quickly and time, which is all we have, must be paid heavily for their acquiring. They are the very simplest things and because it takes a man’s life to know them the little new that each man gets from life is very costly and the only heritage he has to leave. Every novel which is truly written contributes to the total of knowledge which is there at the disposal of the next writer who comes, but the next writer must pay, always, a certain nominal percentage in experience to be able to understand and assimilate what is available as his birthright and what he must, in turn, take his departure from." -H