I started reading John Stuart Mill's Autobiography this week, and it's terrific. Mill had a unique childhood filled with self-education and, you guessed it–reading! He writes:

He [his father] not only drew my attention to the insight they afforded into Athenian institutions, and the principles of legislation and government which they often illustrated, but pointed out the skill and art of the orator—how everything important to his purpose was said at the exact moment when he had brought the minds of his audience into the state most fitted to receive it; how he made steal into their minds, gradually and by insinuation, thoughts which, if expressed in a more direct manner, would have roused their opposition. Most of these reflections were beyond my capacity of full comprehension at the time; but they left seed behind, which germinated in due season (Emphasis mine).

That's a profound idea. Just because you read something beyond your "capacity of full comprehension" doesn't mean you aren't learning or getting something out of it. Seeds are being deposited, which, in due time, will sprout.

Those seeds won't germinate, though, if they aren't watered, rooted in good soil, and given the proper amount of sunlight. I may be over-extending the analogy here (I don't think I am), but without Mill's continued learning, the seeds he and his father planted at a young age would’ve never germinated. What he learned later in life allowed him to put greater context into what he read when he was younger. Without reading challenging works at a young age, his education may not have been as fruitful and advanced as it was when he was older. Without continuing to read challenging works when he got older, he may have never understood what he read when he was younger. It’s a feedback loop. As you read more, you begin to understand how little you know. As you continue to read more, those blindspots get back-filled, and knowledge begins to compound. You may be studying something for ten years, but nothing clicks until you finally read something that brings it all together in the eleventh. That’s the magic (and the difficulty) with compounding–all the big results are always at the end.

So, keep reading things above your “grade level.” It might not all make sense today, but it will if you keep reading and learning. When that happens, people will wonder how you got so smart. When they ask that, you know your compounding has started paying off. (But don’t let this fool you into thinking you’ve arrived. There’s still a lot you probably don’t know!)