test of time
I just went through more than a hundred papers that I saved to read later almost 8 years ago. Now 90 percent of them looks not worth reading at all.
Standing the test of time is a very efficient filter. You do not have to exert any effort at all. Just put the issue on hold for some time and it resolves itself.
Isn't that just magical?
Now that I got into the mood, I decided to go through my actual physical library as well. Half an hour later I discarded around 40 books while repeatedly whispering myself "Why did I even read this shit?"
Letting the society figure out the best out there is also a very powerful tool. Although the societal filter may not exactly match your tastes and interests, due to its greater longevity, it is much more efficient than yours.
How many 1000 years-old books do we still find worth reading today? 10? 20? I have no idea but it is a very small number compared to the actual number of books written.
Today, around 2-3 million books are published worldwide every year. 99.99 percent of them is crap and contains absolutely no universal truths about the human kind or the physical universe. Slowly or not, they will all die off. (Even scientific facts have an average life-time of 45 years.)