Lines of force (or for the hippies, auras)

When I had a chess coach, he frequently instructed me to imagine 'lines of force' emanating from my long-range pieces. Imagine the lines going through all squares, even those presently obstructed by material (I mentioned it here). This seems to be quite common amongst masters, and I have found it helpful. It helps me recognize pins, discovered attacks, and gives me ideas for which lines I want to open up with sacrifices or pawn moves when it is time to attack.

Imagining lines of force is not unique to my coach. Buckley, in his inconsistent Practical Chess Analysis, advises readers to imagine that pieces have "auras." He says:

[T]o see ahead, you first need to know the squares to which a piece may move...These potential moves enliven the piece, giving it an "aura." The aura refers to the array of squares available to the piece...

The aura is unaffected by obstructions. Think of the piece as if it were on an open board. Try to fuse the piece to its aura. The idea is simply that potential moves determine the value of any piece, and the aura comprises just those moves.

Buckley says this aura-visualization habit is a great way to improve your analysis skills, making it less likely that you will miss potential moves as you visualize the game tree in your mind. As you visualize the game tree, be sure you are 'adjusting the auras of the pieces that move. Let each new position soak into your imagination.' This makes it less likely that you will miss certain moves that people often overlook (e.g., horizontal rook moves).

Finally, we have a gorgeous demonstration of this phenomenon well before it was articulated by chess enthusiasts. In 1894, Alfred Binet (who invented the IQ test) published a book Mnemonic Virtuosity: A Study of Chess Players. One aspect of the study involved having masters literally draw what their mental image of a remembered position "looked like" in their heads. The following is one such diagram (position on left, diagram by master on right):
Gorgeous, eh? The little jester on c1 is the Bishop.

What we see are lines that pass through pieces and project to important parts of the board. These aren't exactly the lines of force or auras, as the lines don't project everywhere possible, but only along key squares. The position is stripped of almost all detail. No black and white squares (indeed, the black and white squares are not essential to chess, and initially chess boards had all squares with the same color), not even particular pieces labeled.

The abstract nature of the mental image seems to reinforce the idea that blindfold chess is not a great technique for regular chess improvement (I discussed this a bit here). It also seems that those study methods which have you memorize square colors are not very helpful. Such details are not particularly relevant for the position, and when visualizing moves you don't want to add a bunch of clutter. You want to visualize only the essential details. I have heard people say when they visualize moves, they try to visualize the 'woody grain' of the pieces, how the Knight looks, that sort of thing. This seems worse than unhelpful, since it adds additional load to an imagination that already has plenty of relevant details to think about.

These themes will come up again in my summary of Chapter 6 of Rowson's book Chess for Zebras.

Note I learned about the above Binet study in Shenk's book The Immortal Game (overall the book is just OK, but does include some interesting historical tidbits I hadn't seen before). The above image is taken from page 125 of his book.