It's not really a matter of "getting a hold of" an essence; it's more about understanding something's nature more fully than you did before.
I deliberately left this piece with a very minimal look — this is neither a pencil sketch nor a draft. The only colors are minor, being rendered in CG. I used Deletor pens for the lines (Maru- and Saji-pen tips), so that the lines would be fine and delicate. They had to be that way since I knew this wasn't going to be colored with any watercolors or acrylics at all. The shading was done with a plain-old 2HB pencil. Finally, I slightly modified the brightness and contrast.
This isn't really about a single subject: drawing, writing, sculpture, mathematics, or what-have-you. Insight will strike you whenever and wherever it does, if you put in the time.