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# Full text

Title
International cooperation and technology transfer
Author
Mussio, Luigi

Usase of connectives is a part of propositional calculus
which allows assertions like: the book is on the table, or
“if Socrates is a man, then he is mortal”.
Actually, the meaning of connections is used in order to
defend their natural interpretation, so that, if X and Y are
two statements:
X a Y is true when both X and Y are true: otherwise it is
false
X v Y is true if X is true or Y is true or both
X -, is true when X is false, and is false when X is true
X -> Y the truth of X implies that Y is true
X = Y is true if both X and Y are true, or both X and Y
are false.
From syntactic combination of variables and connectives,
one can build sentences of propositional logic, just like
the expressions of mathematics. In the propositional
calculus, one also encounters the first rules of inference.
An inference rule allows for the deduction of a new
sentence from previously given sentences: the new
sentence is assured to be true, if the previous sentences
(X a (X -> F)) F
were true. An example of inference rule is the
“-»’’elimination rule:
the buildings denote the human settlements
the schools belong to the class of buildings
the schools are located inside the human settlements.
For the purposes of AI, propositional logic is not very
useful. In order to capture in a formalism the world , one
needs not only express true or false sentences, but also to
speak about objects: the predicate calculus is an extension
of the propositional calculus.
Statements about individuals are called predicates', a
predicate has a value of either true or false, where
individuals are used: the school is a building or the
railways is a building.
Use of quantifiers V and 3 implies the introduction of
four inference rules; if:
0(A)
V can be eliminated:
VX.&(X)
all rivers have an end-point;
the Po is a river;
the Po has an end-point.
Functions return objects related to their arguments: the
function capital of, when applied to the individual Italy
returns the value Rome. The predicate calculus, with
addition of functions, and the predicate equals is called
First Order Logic.
Various Artificial Intelligence systems use logic to
represent knowledge, but it is to keep in mind that,
besides logical formalism, also other formalisms are
available:
■ procedural representation
■ semantic networks
■ production systems
■ direct representations.
Discrimination between declarative and procedural
representations of knowledge played an important role in
development of AI. Declarative representations state the
static pattern of knowledge (facts involving subjects,
events and their intercourse) Procedural representations
refer to usage of knowledge (how to find basic facts, or
draw conclusions). All computation programs include
some type of procedural knowledge.
4. Modern Linguistics
Modem Linguistic is commonly said to originate as late
as the V century b.c., although in the proper sense, its
birth may be place much close to the present , that is
about 1916 (de Saussure), or even 1926 (Trubeckoj):
according to the philosophical viewpoint, also Chomsky
(1956) may be taken as one of the founders of this
discipline. Actually, Linguistics is a complex of
comparatively antique notions, however organized only
in quite recent times.
The interest for Sanskrit which peaked for some decades,
after Von Humboldt (1786-1816), gave a remarkable
impulse to what one nowerdays is called Lingusitics, as it
originated comparative grammar, taking into account
some methods derived in the same period for natural
sciences.
However de Saussure upset the historical viewpoint of
studies about language, clearly declaring that the basis of
Linguistics relies upon the study of real working of
language. The primary item is unity: de Saussure, in fact,
tried to individuate the real units which make up the so
called chaine-parlee, the units of code that make the
messages is called structural analysis.
A further step in this analysis is the subdivision of
chaine-parlee, in elementary, individual units, from the
phonic point of view. This way, the basic concept of
phoneme comes to light as found by Trubeckoj (1890-
1938). The reconaissance, as identical units, of all the
single i spoken by all possible voices. So, phonemes are
signs, which work opposite to each other, in order to
discriminate different meanings.
Natural language has a double articulation of speech.
Units of first articulation of language, the ones which
compose the message, may be brought to light: such units
are called monemes and their individuation is easier than
definition of speech.
Messages of natural languages also hold a further
articulation: monemes are, in their turn, decomposed in
smaller units which can be detected by commutation.
Those minimal units which have a phonic form, but no
ordinary meaning are the minimal elements of the second
articulation: they are properly the phonemes, as found by
Trubeckoj (incidentally, he too of Pregel club, like
Jakobson).
The said structure of a double, superimposed code has
been hitherto found only in the natural human languages.
Mathematics, also mathematical logics, are
communication systems for which minimal units of the
message are meaningful, with a form and a semantic