The most learned person says he knows the least, while the least learned person will be totally ignorant of the things he doesn't know.
Thus, it's aptly said that- "He who knows what he doesn't know, is the wisest"
Another aspect of learning is, how it rises exponentially.
We take 3-4 years to learn to make simple lines. It takes us 1 year to learn alphabets in the Kinder Garten. Then, in the next few years we have lesrnt 2-3 languages and basic arithmetics.
In your secondary school, you learn entire subjects within semesters. And now, looking at the books of degree college, 10th std science text book seems to small. When Guyton seemed to difficult to carry because of the size, we hadn't seen Robins which could break backs. And then you reach the level of Harrison's and Bailey & Love, the heavy voices in their fields, little do we anticipate the gargantuan volumes of Review and MCQ books we ll have to solve. And it keeps getting bigger.
Science text book in SSC,
Biology text book in HSC,
Harrison in MBBS,
Braunwalds for Cardiology
ECG book for further studies and the list goes on
The scope of book becomes smaller, but the size keeps getting bigger. However the time taken to complete gets lesser.
