We all have our own personal drawing styles and rules which we follow without thinking. I've picked up good and bad habits along the way, and continue to learn every time I put pencil to paper. It's fascinating though when you stumble across technical knowledge from the past that chimes so strongly with the way you work now.
Here are a couple of examples:
The first is an extract from a letter by Vincent Van Gogh to fellow artist Anton Van Rappard between 1881 & 1885.
"He (Delacroix) had a discussion with a friend about the question of working absolutely after nature, and he said on this occasion that one must get one's studies from nature but that the ultimate picture ought to be made from memory. That friend was walking with him when they were having this discussion - which had already become pretty vehement. When they parted company, the other one still wasn't entirely convinced. Delacroix let him toddle on for a bit after he took his leave, and then (using his two hands as a speaking trumpet) he roared after him in a lusty voice, to the consternation of the respectable citizens passing by, "Par coeur! Par coeur!" (From memory!)
Another thing - the painter Gigoux comes to Delacroix with an antique bronze and asks his opinion about it's genuineness. "It is not from antiquity, it is from the renaissance," says D. Gigoux asks him what reason he has for saying this - "Look here, my friend, it is very beautiful, but it is starved from lines, and the ancients started from central things (the masses, the nuclei)." And he adds:"Look here a moment," and he draws a number of ovals on a piece of paper - and he puts these ovals together by means of little lines, hardly anything at all, and out of this created a rearing horse full of life and movement. "Gericault and Gros," he says, "have learned this from the Greek - to express the masses (nearly always egg-shaped) first tracing the contours and the action from the position and the proportions of these oval shapes"
Now I ask you isn't this a superb truth?"
I couldn't agree with Mr. Van Gogh more. When I first read this last year I was astounded to realise that the way I always draw, and especially when I'm rough keying animation, is exactly as is described in this letter. I'm using the same technique to create movement and form as the ancient Greeks, and it still works every time.
Most "How to Draw" books on cartoons use a version of this but I've yet to see one that I'd really recommend. They have a slightly dishonest way of reverse engineering a drawing back to a series of circles that don't help the reader. A new one of these books shows readers how to draw the Simpsons. Don't believe them, the book will teach you nothing about drawing.
Van Gogh's earlier mention of working from memory keys into the way Japanese artists used to work. They didn't follow the Western school of study for art which was based on copying from life, sat infront of whatever your subject may be, and recording it in as much detail as possible. The Japanese school was about observation of nature without recording. I've read of artists watching birds, for example, for two or more hours without putting a brush to paper, and then turning away and drawing from memory, capturing the essence, spirit and movement in simple expressive strokes. It's a fascinating way to work, and one that I've been using in one way or another since I first started to draw, without realising the history of the technique. I very rarely use sketchbooks on location, but I observe intently and can draw anything from memory. I used this technique recently at a life drawing group. Not putting pen to paper until the last minute of the pose, but just observing prior to that. The resultant drawings were simple but strongly posed and weighted, a distillation of the subject.