In the real world, we are enlightened from some concepts and phenomena such as “biosphere”, “food chain”, “ecological balance” etc. With research and practice, by using the theory of multilateral matrices [
Let 
be a non-empty set and define its cross product as
. A generalized relation of 
is a non-empty subset
. TCE mainly researches generalized relation rules for general 
rather than for special
.
For a relation set
, define both an inverse relationship of 
and a relation multiplication between 
and 
as follows:
And
there is at least an 
such that 
and
.
The relation 
is called reasonable if
. A generalized reasoning of general 
is defined as for 
there is a relation 
such that
.
The generalized reasoning satisfies the associative law of reasoning, i.e.,
. This is the basic requirement of reasoning in TCE. But there are a lot of reasoning forms which do not satisfy the associative law of reasoning in Western Science. For example, in true and false binary of proposition logic, the associative law does not hold on its reasoning because
Let 
be a non empty set and 
be its a relation. We call it an equivalence relation, denoted by
, if the following three conditions are all true:
1) Reflexive: 
for all
, i.e.,
;
2) Symmetric: if
, then
, i.e., if
, then
;
3) Conveyable (Transitivity): if
, then
, i.e., if 
then 
Furthermore, the relation
is called a compatibility relation if there is a non-empty subset 
such that 
satisfies at least one of the conditions above. And the relation 
is called a non-compatibility relation if there doesn’t exist any non-empty subset 
such that 
satisfies any one of the conditions above. Any one of compatibility relations can be expanded into an equivalent relation to some extent [
Western Science only considers the reasoning under one Axiom system such that only compatibility relation reasoning is researched. However there are many Axiom systems in Nature. Traditional Chinese Science mainly researches the reasoning among many Axiom systems in Nature. Of course, she also considers the reasoning under one Axiom system but she only expands the reasoning as the equivalence relation reasoning.
Equivalent relations, even compatibility relations, cannot portray the structure of the complex systems clearly. For example, assume that 
and 
are good friends and they have close relations. So are 
and
. However, you cannot get the conclusion that 
and 
are good friends.
We denote 
as that 
and 
have close relations. Then the example above can be denoted as:
, 
do not imply
, i.e., the relation 
is a non-conveyable (or non-transitivity) relation, of course, a non-equivalent relation. In the following, we consider two non-compatibility relations.
In TCE, any Axiom system is not considered, but should first consider using a logic system. Believe that the rules of Heaven and the behavior of Human can follow the same logic system (天人合一). This logic system is equivalent to a group of computation. The method is to take the research object classification following the selected logic system, without considering the specific content of the research object, namely classification taking images (比类取象). Analysis of the relationship between research objects, make relationships with computational reasoning comply with the selected logic system operation, and then in considering the research object of the specific content of the conditions, according to the logic of the selected system operation to solve specific problems. In mathematics, the method of classification taking images is explained in the following Definition 2.1.
Definition 2.1. Suppose that there exists a finite group
of order 
where 
is identity.
Let 
be a none empty set satisfying that
where the notation means that 
, 
(the following the same). The 
is called a factor image or data image of group element 
for any 
if 
is factor or data.
Denoted
, where the note 
is the usual Cartesian product or cross join. Define relations
where 
is called an equivalence relation of 
if 
is identity; denoted by
; 
is called a symmetrical relation of 
if
; denoted by 
or 
; 
is called a neighboring relation of 
if
;denoted by 
or
;
is called an alternate (or atavism) relation of 
if
; denoted by 
or
.#
In this case, the equivalence relations and symmetrical relations are compatibility relations but both neighboring relations and alternate relations are non-compatibility relations. For the given relation set
these relations are all reasoning relations since the relation 
if
.
The equivalence relation
, symmetrical relations
, neighboring relation 
and alternate relations 
are all the possible relations for the method of classification taking images. In this paper, we mainly consider the equivalence relation
, neighboring relation 
and alternate relations
.
There is an unique generalized reasoning between the two kinds of opposite non-compatibility relations for case
. For example, let 
be a none empty set, there are two kinds of opposite relations: the neighboring relation
, denoted 
by 
and the alternate (or atavism) relation
, denoted 
by
, the logic reasoning architecture [2-19] of “Yin Yang Wu Xing” Theory in Ancient China is equivalent to the following reasoning:
1) If
, 
, then
;
if
, 
, then
;
if
, 
then
;
2) If
, 
, then
;
if
, 
, then
;
if
, 
, then
.
The reasoning is also equivalent to the following calculating
where
, 
and the 
is the addition of module 5.
The two kinds of opposite relations can not be exist separately. Such reasoning can be expressed in
Let 
be a none empty set with the equivalent relation
, the neighboring relation 
and the alternate relations 
denoted by
,
and
, respectively. Then a genetic reasoning is defined as follows:
1) if 
, then
;
2) if 
, then
;
3) if
, 
, then
;
4) if
, 
, then
.
The reasoning is also equivalent to the following calculating
where 
is a finite group of order
. The genetic reasoning is equivalent to that there is a group 
with the operation * such that 
can be cut into 
where 
may be an empty set and the corresponding relations of reasoning can be written as the forms as follows
Satisfying
.
For a none empty set 
and its a relation set
, the form 
(or simply,
) is called a multilateral system [2-19], if 
satisfies the following properties:
1) 
i.e.
.
2) 
3) The relation 
if
.
4) For
, there is a relation 
such that
.
The 4) is called the reasoning, the 1) the uniqueness of reasoning, the 2) the hereditary of reasoning (or genetic reasoning) and the 3) the equivalent property of reasoning of both relations 
and
, i.e., the reasoning of 
is equivalent to the reasoning of
. In this case, the two-relation set 
is a lateral relation of
. The 
is called an equivalence relation. The multilateral system 
can be written as
. Furthermore, the 
and 
are called the state space and relation set considered of
, respectively. For a multilateral system
, it is called complete (or, perfect) if “
” changes into “=”. And it is called complex if there exists at least a non-compatibility relation
. In this case, the multilateral system is also called a logic analysis model of complex systems.
Let 
be a non-compatibility relation. A complex multilateral system
is said as a steady multilateral system (or, a stable multilateral system) if there exists a number 
such that 
where
. The condition is equivalent to there is a the chain 
such that
, or 
. The steady multilateral system is equivalent to the complete multilateral system. The stability definition given above, for a relatively stable system, is most essential. If there is not the chain or circle, then there will be some elements without causes or some elements without results in a system. Thus, this system is to be in the state of finding its results or causes, i.e., this system will fall into an unstable state, and there is not any stability to say.
Theorem 2.1. The system 
is a multilateral system if and only if there exists a finite group 
of order 
where 
is identity such that the relation set 
satisfying
.#
In this case, the multilateral system 
can be written as 
satisfying
where 
may be an empty set.
Theorem 2.2. If the multilateral system 
is a steady multilateral system, then 
and 
is a finite group of order 
about the relation multiplication 
where
must be a non empty set.#
Definition 2.2. Suppose that a multilateral system 
can be written as 
satisfying
and
.
The group 
of order 
where 
is identity is called the representation group of the multilateral system
. The representing function of 
is defined as follows
Let multilateral systems 
be with two representation groups
, respectively. Both multilateral systems
are called isomorphic if the two representation groups 
are isomorphic.#
Theorems 2.1 and 2.2 and Definitions 2.1 and 2.2 are key concepts in multilateral system theory because they show the classification taking images as the basic method. In the following, introduce two basic models to illustrate the method.
Theorem 2.3. Suppose that 
with multiplication table
i.e., the multiplication of 
is the addition of module 2. In other words,
.
And assume that
satisfying
.
Then 
is a steady multilateral system with one equivalent relation 
and one symmetrical relation 
which is a simple system since there is not any non-compatibility relation. In other words, the relations
’s are the simple forms as follows:
, 
where 
is corresponding to
. #
It will be proved that the steady multilateral system in Theorem 2.3 is the reasoning model of “Tao” (道) in TCE if there are two energy functions
and 
satisfying
, called Dao model, denoted by
.
Theorem 2.4. For each element 
in a steady multilateral system 
with two non-compatibility relations, there exist five equivalence classes below:
Which the five equivalence classes have relations in
It can be proved that the steady multilateral system in Theorem 2.4 is the reasoning model of “Yin Yang Wu Xing” in TCE if there are five energy functions (Defined in Section 3) 
and 
satisfying
Called Wu-Xing model, denoted by
.
By Definition 2.2, the Wu-Xing model 
can be
written as follows:
Define
corresponding to wood, fire, soil, metal, water, and assume
and
satisfying
i.e., the relation multiplication of 
is isomorphic to the addition of module 5. Then 
is a steady multilateral system with one equivalent relation 
and two non-compatibility relations 
and
.
These Theorems can been found in [1-6,11-16]. 
with two non-compatibility relations is equivalent to the logic architecture of reasoning model of “Yin Yang Wu Xing” Theory in Ancient China. What describes the general method of complex systems can be used in economic complex system.
which makes every subsystem meaningful of the multilateral system.
and 
of multilateral system
, denote 
(or
, or
, or
) means 
(or
, or
, or
).
and 
where 
. Let
, 
and 
be the energy function of
, the energy function of 
and the total energy of both 
and
, respectively.
, if 
(the normal state of the energy of
), then the neighboring relation 
is called that 
likes 
which means that 
is similar to
. In this case, the 
is also called the brother of 
while the 
is also called the brother of
. In the causal model, the 
is called the similar family member of 
while the 
is also called the similar family member of
. There are not any causal relation considered between 
and
.
, if
) where the 
is an interaction of 
and 
satisfiing
, then the symmetrical relation
is called that 
is corresponding to 
which means that 
is positively (or non-negatively) corresponding to 
if 
(or
) and that 
is negatively corresponding to 
if
. In this case, the 
is also called the counterpart of 
while the 
is also called the counterpart of
. In the causal model, the 
is called the reciprocal causation of 
while the 
is also called the reciprocal causation of
. There is a reciprocal causation relation considered between 
and
.
, if 
(the normal state of the energy of
), then the neighboring relation 
is called that 
bears (or loves) 
[or that 
is born by (or is loved by)
] which means that 
is beneficial on 
each other. In this case, the 
is called the mother of 
while the 
is called the son of
. In the causal model, the 
is called the beneficial cause of 
while the 
is called the beneficial effect of
.
, if
(the normal state of the energy of
), then the alternate relation 
is called as that 
kills (or hates) 
[or that 
is killed by (or is hated by)
] which means that 
is harmful on 
each other. In this case, the 
is called the bane of 
while the 
is called the prisoner of
. In the causal model, the 
is called the harmful cause of 
while the 
is called the harmful effect of
.
is a steady multilateral system having energy, then 
in the multilateral system during normal operation, its energy function for any subsystem of the multilateral system has an average (or expected value in Statistics), this state is called normal when the energy function is nearly to the average. Normal state is the better state.
with two non-compatibility relations, suppose that there is an external force (or an intervening force) on the subsystem 
of 
which makes the energy 
of 
changed by the increment
, then the energies
, 
, 
, 
of other subsystems
, 
, 
, 
(defined in Theorem 2.4) of 
will be changed by the increments
, 
, 
and
, respectively.
of multilateral system 
is intervened, then the energies of the subsystems 
and 
which have neighboring relations to 
will change in the same direction of the force outside on
. We call them beneficiaries. But the energies of the subsystems 
and 
which have alternate relations to 
will change in the opposite direction of the force outside on
. We call them victims.
changes in the same direction of
, and any harmful subsystem of 
changes in the opposite direction of
. The size of the energy changed is equal, but the direction opposite.
, the energy increment (or, increase degree) 
of the son 
of 
is greater than the energy increment 
of the mother 
of
, i.e., the best beneficiary is the son 
of
. But the energy decrease degree 
of the prisoner 
of 
is greater than the energy decrease degree 
of the bane of
, i.e., the worst victim is the prisoner 
of
.
, the energy decrease degree 
of the mother 
of 
is greater than the energy decrease degree 
of the son of
, i.e., the best beneficiary is the mother 
of
. But the energy increment 
of the bane 
of 
is greater than the energy increment 
of the prisoner 
of
, i.e., the worst victim is the bane
of
.
, then
, 
, 
,
;
, then
, 
, 
,
;
. Both 
and 
are called intervention reaction coefficients, which are used to represent the capability of intervention reaction. The larger 
and
, the better the capability of intervention reaction. The state 
is the best state but the state 
is the worst state.
has been intervened, then the energy of subsystem which has neighboring relation changes in the same direction of the force, and the energy of subsystem which has alternate relation changes in the opposite direction of the force. The size of the energy changed is equal, but the direction opposite.
and 
are decreasing functions of the intervention force 
since the intervention force 
is easily to transfer all if 
is small but the intervention force is not easily to transfer all if 
is large. The energy functions of complex system, the stronger the more you use. In order to magnify 
and
, should set up an economic society of the intervenetion reaction system, and often use it.
and 
are too small. In the state
, any economic intervening resistance problem is non-existence but in the state
, economic intervening resistance problem is always existence. At this point, the paper advocates the essential principle of intervening to avoid economic intervening resistance problems.
of a steady multilateral system 
which makes the energy 
changed by increment 
such that the energies 
of other subsystems
, 
, 
, 
(defined in Theorem 2.4) of 
will be changed by the increments
, 
, 
, 
, respectively, then can the multilateral system 
has capability to protect the worst victim to restore?
should be protected by using the same intervention force but any beneficial subsystem of 
should not.
by the increment
, the worst victim is the prisoner 
of 
which has the increment
. Thus the intervening principle of self-protection is to restore the prisoner 
of 
and the restoring method of self-protection is to increase the energy 
of the prisoner 
of 
by using the intervention force on 
according to the intervention rule. In general, the increase degree is 
where
.
by the increment
, the worst victim is the bane 
of 
which has the increment
. Thus the intervening principle of self-protection is to restore the bane
of 
and the restoring method of selfprotection is to decrease the energy 
of the bane 
of 
by using the same intervention force on 
according to the intervention rule. In general, the decrease degree is 
where
.
, then the energy of subsystem 
will decrease the increment
, which is the worst victim. So the capability of self-protection increases the energy of subsystem 
by increment 
where
, in order to restore the worst victim by according to the intervention rule.
, then the energy of subsystem 
will increase the increment
, which is the worst victim. So the capability of self-protection decreases the energy of subsystem 
by increment 
where
, in order to restore the worst victim by according to the intervention rule.
The 
is the intervention reaction coefficient. The 
is called a self-protection coefficient, which is used to represent the capability of self-protection. The larger
, the better the capability of self-protection. The state 
is the best state but the state 
is the worst state of selfprotection. According to the general economy of the protection principle, 
should be not greater than 
since the purpose of protection is to restore the victims and not reward the victims.
is also a decreasing function of the intervention force 
since the worst victim is easily to restore all if 
is small but the worst victim is not easily to restore all if 
is large. The energy function of complex system, the stronger the more you use. In order to magnify
, should set up an economic society of the self-protection system, and often use it.
which has energy function 
and capabilities of intervention reaction and self-protection is with intervention reaction coefficients 
and
, and with self-protection coefficient
. If the capability of self-protection wants to restore both subsystems 
and
, then the following statements are true.
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, then all five subsystems will be changed finally by the increments as follows:
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, then all five subsystems will be changed by the increments as follows:
’s are the increments under the capability of self-protection.#
which has energy function 
and capabilities of intervention reaction and self-protection is with intervention reaction coefficients
and 
, and with self-protection coefficient 
. Then the capability of self-protection can make both subsystems 
and 
to be restored at the same time, i.e., the capability of self-protection is better, if and only if 
and
.#
and
. General for a stable complex system of economic society, the condition 
is easy to meet since it can restore two subsystems by Theorem 3.1, but the condition 
is difficult to meet since it only can restore one subsystem by Theorem 3.1. At this point, the paper advocates the principle to avoid any side effect of intervening.
which has energy function and capabilities of intervention reaction and self-protection is with intervention reaction coefficients 
and
, and with self-protection coefficient 
satisfying 
and
. Then the following statements are true.
of steady multilateral system 
is implemented such that its energy 
increases the increment
, then the subsystems 
, 
and 
can be restored at the same time, but the subsystems 
and 
will increase their energies by the increments
of steady multilateral system 
is implemented such that its energy 
decreases, i.e., by the increment
, the subsystems
, 
and 
can also be restored at the same time, and the subsystems 
and 
will decrease their energies, i.e., by the increments
which has energy function 
and capabilities of intervening reaction and self-protection, assume intervention reaction coefficients are 
and
, and let the self-protection coefficient be
, which satisfy
, 
and 
where 
(the following the same) is the solution of
. Then the following statements are true.
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, then the final increment 
of the energy 
of the subsystem 
changed is greater than or equal to the final increment 
of the energy 
of the subsystem 
changed based on the capability of self-protection.
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, then the final increment 
of the energy 
of the subsystem 
changed is less than or equal to the final increment 
of the energy 
of the subsystem 
changed based on the capability of selfprotection. #
which has energy function 
and capabilities of intervening reaction and self-protection, assume intervention reaction coefficients are 
and
, and let the self-protection coefficient be
, which satisfy 
, 
and
. Then the following statements are true.
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, then the final increment 
of the energy 
of the subsystem 
changed is less than the final increment 
of the energy 
of the subsystem 
changed based on the capability of self-protection.
of steady multilateral system V is implemented such that such that its energy 
has been changed by increment
, then the final increment 
of the energy 
of the subsystem 
changed is greater than the final increment 
of the energy 
of the subsystem 
changed based on the capability of selfprotection.#
, 
and 
since in this time,
.
which has energy function 
and capabilities of intervention reaction and self-protection is with intervention reaction coefficients
and 
, and with self-protection coefficient 
. Then the following statements are true.
and 
of 
with an alternate relation such that 
encounters virtual disease, and at the same time, 
befalls real disease. If an intervention force on the subsystem 
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, and at the same time, another intervention force on the subsystem 
of steady multilateral system 
is also implemented such that its energy 
has been changed by increment 
, then all other subsystems:
, 
and 
can be restored at the same time, and the subsystems 
and 
will increase and decrease their energies by the same size but the direction opposite, i.e., by the increments
and 
of 
with an alternate relation such that 
encounters real disease, and at the same time, 
befalls virtual disease. If an intervention force on the subsystem 
of steady multilateral system 
is implemented such that its energy 
has been changed by increment
, and at the same time, another intervention force on the subsystem 
of steady multilateral system 
is also implemented such that its energy 
has been changed by increment
, then all other subsystems:
, 
and 
can be restored at the same time, and the subsystems 
and 
will decrease and increase their energies by the same size but the direction opposite, i.e., by the increments
, 
and 
since
.
as the same category, the neighboring relation 
as beneficial, harmony, obedient, loving, etc. and the alternate relation 
as harmful, conflict, ruinous, killing, etc., then the above defined stable logic analysis model is similar to the logic architecture of reasoning of “Yin Yang Wu Xing”. Both “Yin” and “Yang” mean that there are two opposite relations in the world: harmony or loving 
and conflict or killing
, as well as a general equivalent category
. There is only one of three relations
, 
and 
between every two objects. Everything 
makes something
, and is made by something
; Everything restrains something
, and is restrained by something
; i.e., one thing overcomes another thing and one thing is overcome by another thing. The ever changing world
, following the relations:
, 
and
, must be divided into five categories by the equivalent relation
, being called “Wu Xing”: wood (
), fire (
), soil (
), metal (
), water (
). The “Wu Xing” is to be “neighbor is friend”: wood (
)
fire (
)
soil (
)
metal (
)
water(
)
wood (
), and “alternate is foe”: wood (
)
soil (
)
water (
)
fire (
)
metal (
)
wood(
). In other words, the ever changing world must be divided into five categories:
) = {industry, legislature, cognitive, structure, goods, spring, birth}; fire (
) = {agriculture, administrative institutions, development, fluctuations, foods, summer, growth }; soil (
) = {commerce, media organizations, coordination, harmonious, money, long-summer, combined}; metal (
) = {education, non-governmental institutions, function, quality, knowledge, autumn, accept}; water (
) = {army, supervisory organ, risk, cost, weapons, winter, hiding}.
becomes larger, then the loving force is large and the force of similar material accumulation of each other is also large. They can make the economic complex system more stable. If the killing force is small, i.e., 
becomes smaller, then the loving force is small and the force of similar material accumulation of each other is also small. They can make the economic complex system becoming unstable.
. In this time, the energy of the system will be the sum of energy of each part. Thus the economic system will be a simple economic system which is not what we consider range.
and 
near to 0. The state 
is the worst state of the economic society system, namely Economic Crisis. On the way, the economic intervening resistance problem will occur since any economic intervening method is possible too little for some small 
and
.
itself directly when
, 
and
. In this case:
, 
and 
but should be used as little as possible.
and 
near to 1. The state 
is the best state of the economic society system. On the way, it is almost none economic intervening resistance problem since any economic intervening method is possible good for some large 
and
.
falls virtual disease), the local frequently used method is to use industrial keep agriculture (i.e., to increase the energy of 
which is the mother of
). The idea is precisely “Virtual disease for economic downturn is to fill his mother” if one subsystem of economic society falls virtual ill.
satisfies
. In logic and practice, it’s reasonable 
near to 1 since an economic output subsystem is absolutely necessary social other subsystems of all consumption. In case:
, all the energy for intervening economic society subsystem can transmit to other economic society subsystems which have neighboring relations or alternate relations with the intervening economic society subsystem. The condition 
can be satisfied when 
and 
for an economic society since 
implies
is small. A common standard is
, i.e., there is a principle which all losses are bear in economic society. Thus the general condition often is 
Interesting, they near to the golden numbers.
and 
of the economic society system are abnormal (economic downturn or overheating). In the economic society of two noncompatible relations with constraints, only two situations may occur:
encounters virtual disease for economic downturn, and at the same time, 
befalls virtual disease for economic downturn, i.e., the energy of 
is too low and the energy of 
is also too low. It is because 
bears
. The economic downturn causal is
.
encounters real disease for economic overheating, and at the same time, 
befalls real disease for economic overheating, i.e., the energy of 
is too high and the energy of 
is also too high. It is because 
is born by
. The economic downturn causal is
.
, 
and
, if one wants to treat the abnormal subsystems 
and
, then 1) In virtual disease for economic downturn, the one should intervene subsystem 
directly by increasing its energy. It means “virtual disease for economic downturn is to fill his mother” because the economic downturn causal is
;
directly by decreasing its energy. It means “Real disease for economic overheating is to rush down his son” because the economic downturn causal is
.
) is virtual (currency devaluation) and the food (
) is also virtual (inflation of food prices), the local frequently used method is mainly to increase the supply of food (i.e., to increase the energy of 
which is the mother of
), in order to control the price of food cannot rise. The idea is precisely “Virtual disease for economic downturn is to fill his mother” if two loving subsystems 
(as
) and 
(as
) of economic society fall virtual ill.
and 
greater and near to 1. The state 
is the best state of the economic society system. On the way, it almost have none economic intervening resistance problem since any economic intervening method is possible good for some large 
and
.
and 
of an economic society system are abnormal (economic downturn or overheating). In the economic society system with the constraints of two non-compatible relations, only a situation may occur: 
encounters virtual disease for economic downturn, and at the same time, 
befalls real disease for economic overheating, i.e., the energy of 
is too low and the energy of 
is too high. The disease is serious because 
has harmed the 
by using the method of incest such that the king relation between 
and 
is damaged.
, 
and
, if one wants to treat the abnormal subsystems 
and
, the one should intervene subsystem 
directly by increasing its energy, and at the same time, intervene subsystem 
directly by decreasing its energy. It means that “Strong inhibition of the same time, support the weak”.
falls virtual disease and at the same time, 
befalls real disease. The disease is serious because 
has harmed the 
by using the method of incest such that 
cannot kill
, which has damaged the king relation between 
and 
of the economic society. The condition that
, 
and 
can think it is true since the economic society is not rich although social intervention response ability and self-protection ability is good. In order to cure the serious disease, Deng XiaoPing’s taking method is to break the “iron bowl” (to fill up
, strengthen legislation and industrial income), and to allow a few people to get rich (to rush down
, abate the coordinated ability). The idea is “Strong inhibition of the same time, support the weak” if 
falls virtual disease and at the same time, 
befalls real disease.
and 
greater and near to 1. The state 
is the best state of the steady multilateral system. On the way, it almost have none economic intervening resistance problem since any economic intervening method is possible good for some large ρ3 and ρ1.
, 
and
, according to the intervening principle of “Real disease for economic overheating is to rush down his son but virtual disease for economic downturn is to fill his mother”. The intervention method directly can be used in case:
, 
and 
but should be used as little as possible.