14
The connection between mental and material
systems is rather close in the society.
Deciding, for example, whether a scientific
theory is true or not is mostly related to the practical activity of scientists (experiments, measurements) then on the basis of the true theory its
utilisable elements are brought to the society that
organises its activities accordingly.
The practical consequences of religion systems could be even more well-known. Hundreds
of millions of people act according to religious
rituals based on a concept system and these acts
influence material systems: e.g. building
churches, idols (acquisition of stone and wood
material from the natural environment), millions
dipping in the holy water of Ganges River (releasing billions of bacteria into the water), etc.
A legal regulation system can be regarded as a
mental system until it becomes authoritative.
Following this, the power administration of the
given society forces citizens to perform practical
acts. This interaction is illustrated by forming the
environmental act of a country, making it authoritative and executing it. In the above case changing the human acts impeding or disturbing the
natural operation of environmental systems can
be expected from the indirect effects of the mental system performed via state administration.
Systems can also be classified according to
their relation to their environment. From this
aspect the fact whether there is material and
energy exchange between the given system and
its environment has to be studied. Material systems transporting and taking no material or
energy to and from its environment are called isolated systems. Such systems can be formed practically only in laboratories and it is hard as
complete insulation is a great technical task.
The second type of systems take and release
energy but no material exchange can be observed.
Such systems are called closed systems that are
very rare on Earth (Fig. 2.3).
Naturally, open systems have material and
energy exchange with their environment; moreover, in the case of ecological and social systems
information flow also takes place (Fig. 2.3).
Environmental systems on the Earth are therefore
open systems.
Differences between open and closed systems
seem to be clear and simple based on the above
definitions, in reality, however, making difference between the two types of systems is not
always so simple.
First of all, we have to step back to material
and energy flow. Let us imagine a city which is a
relatively complex material system: it is composed of natural and artificial elements (soil,
plants, animals, humans, roads, buildings, industrial factories, etc.). The city receives a vast
amount of energy via solar radiation (which is
partly radiated back into space) and many goods
are transported into the city each day while goods
produced in the city are transported into other cities. Material in- and outflow is clear and even
store have energy content. This city, however,
cannot exist for long (together with people living
there!) if no energy inflow appears from energy
sources that can be directly utilised for the operation of the city, like electricity, natural gas, petrol,
oil, etc.
Even though the energy arrives in the above
forms the city would not survive for long if all
transport of goods would be stopped and inhabitants could not obtain food or water. This means
that the system will be closed in relation to material essential regarding the operation of the system. A town under blockade, for example, has to
be regarded practically a closed system until the
blockade is on.
In our opinion a system is practically closed
when the forms of energy or material essential
for the operation of the system cannot enter the
system (crossed arrows in Fig. 2.3) and thus their
operation is possible only for a limited time.
Closed social systems are somewhat different.
For example, North Korea is a closed (communist) system country. This does not mean completely missing material and energy (or even
information) flow but means their strong
limitation.
The global system of planet Earth is again different regarding openness. Regarding it a solely
physical system it is clearly an open system since
enormous amounts of material and energy arrives
to (solar radiation, cosmic radiation, cosmic dust,
meteorites) and leaves (energy radiated back to
2 Structure and Operation of Systems, Models of the Global Earth System
The connection between mental and material
systems is rather close in the society.
Deciding, for example, whether a scientific
theory is true or not is mostly related to the practical activity of scientists (experiments, measurements) then on the basis of the true theory its
utilisable elements are brought to the society that
organises its activities accordingly.
The practical consequences of religion systems could be even more well-known. Hundreds
of millions of people act according to religious
rituals based on a concept system and these acts
influence material systems: e.g. building
churches, idols (acquisition of stone and wood
material from the natural environment), millions
dipping in the holy water of Ganges River (releasing billions of bacteria into the water), etc.
A legal regulation system can be regarded as a
mental system until it becomes authoritative.
Following this, the power administration of the
given society forces citizens to perform practical
acts. This interaction is illustrated by forming the
environmental act of a country, making it authoritative and executing it. In the above case changing the human acts impeding or disturbing the
natural operation of environmental systems can
be expected from the indirect effects of the mental system performed via state administration.
Systems can also be classified according to
their relation to their environment. From this
aspect the fact whether there is material and
energy exchange between the given system and
its environment has to be studied. Material systems transporting and taking no material or
energy to and from its environment are called isolated systems. Such systems can be formed practically only in laboratories and it is hard as
complete insulation is a great technical task.
The second type of systems take and release
energy but no material exchange can be observed.
Such systems are called closed systems that are
very rare on Earth (Fig. 2.3).
Naturally, open systems have material and
energy exchange with their environment; moreover, in the case of ecological and social systems
information flow also takes place (Fig. 2.3).
Environmental systems on the Earth are therefore
open systems.
Differences between open and closed systems
seem to be clear and simple based on the above
definitions, in reality, however, making difference between the two types of systems is not
always so simple.
First of all, we have to step back to material
and energy flow. Let us imagine a city which is a
relatively complex material system: it is composed of natural and artificial elements (soil,
plants, animals, humans, roads, buildings, industrial factories, etc.). The city receives a vast
amount of energy via solar radiation (which is
partly radiated back into space) and many goods
are transported into the city each day while goods
produced in the city are transported into other cities. Material in- and outflow is clear and even
store have energy content. This city, however,
cannot exist for long (together with people living
there!) if no energy inflow appears from energy
sources that can be directly utilised for the operation of the city, like electricity, natural gas, petrol,
oil, etc.
Even though the energy arrives in the above
forms the city would not survive for long if all
transport of goods would be stopped and inhabitants could not obtain food or water. This means
that the system will be closed in relation to material essential regarding the operation of the system. A town under blockade, for example, has to
be regarded practically a closed system until the
blockade is on.
In our opinion a system is practically closed
when the forms of energy or material essential
for the operation of the system cannot enter the
system (crossed arrows in Fig. 2.3) and thus their
operation is possible only for a limited time.
Closed social systems are somewhat different.
For example, North Korea is a closed (communist) system country. This does not mean completely missing material and energy (or even
information) flow but means their strong
limitation.
The global system of planet Earth is again different regarding openness. Regarding it a solely
physical system it is clearly an open system since
enormous amounts of material and energy arrives
to (solar radiation, cosmic radiation, cosmic dust,
meteorites) and leaves (energy radiated back to
2 Structure and Operation of Systems, Models of the Global Earth System