You can forget facts but you cannot forget understanding.

The real hallmark of learning is transferring what you’ve learned into new contexts.

Just as you can't become a marathon runner by watching marathons on TV, likewise for science, you have to go through the thought processes of doing science and not just watch your instructor do it.

I thought I was a good teacher until I discovered my students were just memorizing information rather than learning to understand the material.

Lecture is the transfer of the notes of the lecturer to the notes of the student without passing through either.

You can forget facts but you cannot forget understanding.