Author: Howard Exner
Date: 23:40:04 10/04/99
Go up one level in this thread
On October 04, 1999 at 18:41:52, Robert Hyatt wrote:
>On October 04, 1999 at 17:32:27, Howard Exner wrote:
>
>>Here are two respected authors interpretation of sacrifices vs combinations.
>>
>>1. From I.Z. Bondarevsky in "Combinations in the Middlegame"
>>
>>Once we have examined the various sorts of combinations we must devote
>>particular consideration to yet an-other important middlegame question. This
>>chapter will deal with sacrifices. Here the reader might well ask what sort of
>>sacrifices we have in mind, in view of the fact that sacrifices have entered
>>into every example in the book so far.
>>However a separate section on sacrifices is fully justified. The point is that
>>in combinations the sacrifices are always accompanied by forced maneuvers as a
>>result of which the active side gains an objective advantage. Hence the
>>sacrifice was not a sacrifice in the full sense of the word. However, in
>>practical play we often meet with positions in which a player goes in for a
>>sacrifice without being able to calculate all its consequences.
>>About thirty years ago one of the leading Grandmasters of his time,
>>Rudolf Spielmann, a keen combinative player, wrote a book called The Art of
>>Sacrifice in Chess. In this book the author dealt with many of the problems
>>connected with sacrifices on the basis of his wide personal experience.
>>Spielmann called the sacrifices we are going to analyze real sacrifices,
>>emphasizing that they are not of a temporary nature susceptible to accurate
>>analysis. I cannot agree with Spielmann's classification of sacrifices as he
>>liquidates, in effect, a concept of sacrifice which has become firmly
>>established in chess literature all over the world, although it must be admitted
>>that this concept needs to be more refined.
>>
>>Rubinstein vs Spielmann
>>5rk1/1p3rpp/2bpp3/p1q5/1PP1P3/P1QR2P1/6BP/4R2K b - - bm Bxe4;
>>
>>Hence, as Black could not calculate all the consequences of his sacrifice we
>>cannot say that Black has entered on a combination. We encounter, from the point
>>of view of principle, a new phenomenon. There is no accurate calculation, no
>>forced maneuver accompanying the sacrifice, winning back material or leading to
>>mate. Hence it follows that there is no combination according to our
>>understanding of the term. There is only a sacrifice which leads in various
>>forced variations to positions which Spielmann assessed as being in his favor
>>despite his material deficit since the White king is forced into perilous
>>situations. Hence, we repeat, a sacrifice as opposed to a combination is based
>>not on exact calculation but on assessment of the positions to which it leads.
>>One must stress that it is a question here not of the static assessment of a
>>normal position with material equality, but of the assessment of possibilities
>>in a position where the material balance has been disturbed. I call such an
>>assessment a dynamic assessment.
>>
>>Smyslov vs Kotov
>>3r1r2/pp1q2bk/2n1nppp/2p5/3pP1P1/P2P1NNQ/1PPB3P/1R3R1K w - - bm Nf5;
>>
>>Smyslov wrote about his first move "A typical piece sacrifice in such positions.
>>Its special feature in this case is White's attempt not to win back the
>>sacrificed material but to get an attack by systematically increasing pressure.
>>There is no necessity here to calculate concrete variations but l rely upon a
>>general assessment of the position.
>>
>>2. from Mark Dvoretsky in "Secrets of chess Tactics" p116.
>>
>>The word 'sacrifice' is used in chess literature with two different meanings.
>>First of all, this is a move which gives up material. A sacrifice in this sense
>>of the word is, in Botvinnik's opinion, an indispensable element of any
>>combination. ("A combination is a forced variation with a sacrifice)." The
>>second meaning of the word 'sacrifice' relates to the giving-up of material in
>>the absence of a combination-i.e. to a move which is not connected with a chain
>>of precisely calculated variations that lead by force to success for the player
>>making the
>>sacrifice. Spielmann called such sacrifices "real" (as distinct from "apparent",
>>as in the first case) When making a "real" sacrifice a chess player relies on
>>the influence of certain positional factors to compensate for the material given
>>up. But his calculations may in fact not be justified, and therefore real
>>sacrifices are always associated with risk.
>>
>>I thought Dvoretsky summarized it nicely.
>
>
>It would seem that they mesh _exactly_ with what I have been saying about
>the definition of the word all along?
Yes, both these authors loaded their books with numerous examples to
draw a distinction between two kinds of "sacrifices". The "combination"
examples were always the kind that were within the the "vision" of the
one initiating it. All calculated and seen as a temporary giving up
of material in return for some other visualized advantage (mate,material,draw).
They also went to great lengths to describe another kind of move, dubbed
the "real sacrifice" (or positional sacrifice). That was the sequence of
moves that traded material for some other form of compensation
(the dynamic stuff -initiative,pressure,cramping the opponent,maximizing
ones pieces ...), not within the range of calculation.
But within those definitions lie alot of subjectivity. What is a
combination for one person could equally be a sacrifice for another
depending on ones level of calculating depth. What was a finely calculated
combination for Capablanca
would if I were to make the move be a sacrifice (the kind that carried with it
the "risk" that Dvoretsky spoke of). Having the many examples in their books
made their definitions clearer. At all our varying levels of play we make
these kind of moves all the time. The combination that we know will have
a positive return vs the shaky investment of the sacrifice where the
outcome is beyond our mental capacity to visualize( the trade off you
believe will benefit you).
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