Chess Tip Of The Day

It is important to distinguish between 'control' and 'occupation' of the centre. As soon as a piece occupies a central square it loses the control it exerted over this square. Luděk Pachman, Complete Chess Strategy 2: Pawn-Play And The Centre

A defensive sacrifice can prove effective for psychological reasons. The attacker is mentally geared up for a possible sacrificial assault on the enemy king, and then suddenly he is defending and trying to nurse his material advantage to an ending. This requires a complete shift of mental gears, which can prove difficult to achieve. John Nunn, Secrets Of Practical Chess

An advantage in mobility must be exploited energetically (usually by an assault), otherwise it will be dissipated in short order.  Reuben Fine, The Ideas Behind The Chess Openings

The probability of a blunder increases in quiet positions when a player has difficulty in switching from general considerations to a task of calculation that suddenly presents itself. Vladimir Popov, Chess Lessons

The mere occupation of the centre by pawns does not spell control of the centre. So long as the opponent has centre or wing pawns yet to be heard from, centre-control remains in abeyance. Al Horowitz & Geoffrey Mott-Smith, Point Count Chess

Statistics culled from numerous tournaments reveal that rook endings comprise 50% of all endgames, and it is for this reason that a study of them is of great practical value. Grigory Levenfish & Vasily Smyslov, Rook Endings