Transcript PPT - Ubiquitous Computing Lab

Intelligent systems
Colloquium 1
Positive and negative of logic in
thinking and AI.
Description of logic in Wikipedia
Logic (from Classical Greek λόγος (logos), originally meaning the word, or
what is spoken, but coming to mean thought or reason) is most often said to be
the study of arguments, although the exact definition of logic is a matter
of controversy amongst philosophers (see below). However the subject
is grounded, the task of the logician is the same: to advance an account
of valid and fallacious inference to allow one to distinguish good from bad arguments.
Traditionally, logic is studied as a branch of philosophy. Since the mid-1800s
logic has been commonly studied in mathematics, and, even more recently,
in computer science. As a science, logic investigates and classifies the structure
of statements and arguments, and devises schemata by which these are codified.
The scope of logic can therefore be very large, including reasoning about
probability and causality. Also studied in logic are the structure of
fallacious arguments and paradoxes
Objectives
• Genesis of logic and role of logic in
evolution of mind and mankind,
• Logic as kind of semiotic (symbol) system
• Positive role of logic in development of
science and mankind
• Negative role of logic from point of view of
cognitive science
• Logic and creativity
• Role of logic in AI
• Adaptation of logic to new challenges of AI
Submit a questions to discuss
• Logic is enemy of creativity and
understanding of environment
• Logic is tool for making of predictability
and standard of behavior
Description of logic in Wikipedia
Logic (from Classical Greek λόγος (logos), originally meaning the word, or what
is spoken, but coming to mean thought or reason) is most often said to be
the study of arguments, although the exact definition of logic is a matter of
controversy amongst philosophers (see below). However the subject is grounded,
the task of the logician is the same: to advance an account of valid and fallacious
inference to allow one to distinguish good from bad arguments.
Traditionally, logic is studied as a branch of philosophy. Since the mid-1800s logic
has been commonly studied in mathematics, and, even more recently,
in computer science. As a science, logic investigates and classifies the structure
of statements and arguments, and devises schemata by which these are codified.
The scope of logic can therefore be very large, including reasoning about
probability and causality. Also studied in logic are the structure of
fallacious arguments and paradoxes
Genesis of logic and role of logic in
evolution of mind and mankind,
• Reason of appearance of mathematics is
necessity to describe of objects and
phenomenon (it’s quantitative features) by
standard way for monosemantic understanding
during communications
• Reason of appearance of logic is wish to
describe by standard way of qualitative features
of world and of behavior of human during
making of decisions (for monosemantic
understanding and description of standard
decisions, for example, in jurisprudence, in
producing of things - technologies)
• The human can to cut off part of stick
making it of determined size. In this case
he deals with mathematics
• The human can decide to cut off part or
not. In this case he deals with logic.
• Making of decision appears in brain when
quantity transforms to quality, i.e.
stimulation of any neuron became more
then threshold (appearance of motivation,
reason), or any one neuron wins others
(choice of behavior, strategy and so on)
Principle of unity of fuzzy reasoning
and certain operations
• This is one of principles of organization of
intelligent systems [A.Gavrilov, 2003]
• In a basis of reasoning the operating with fuzzy
images lays, at the end of which choice of
certain operation (action) is carried out (restoring
of it), with which it is possible to associate choice
succeeded (the solved task), focusing of
attention, start of operation as programs of
operation motor neurons, etc. Thus selected
operation as tag is involved in the further
process of reasoning.
Thus, it is possible to extract the several key "intelligent inventions“
and consider the sequence of achievements of biological evolution (Fig. 2).
The abilities to cognize the natural phenomena is gradually increased in this
sequence.
Logic as kind of semiotic (symbol)
system
S=<B,F,A,R>,
where:
B – alphabet,
F – formulas-facts;
A – formulas-axioms,
R – rules of inference.
A logic allows the axiomatization of the domain information, and the
drawing of conclusions from that information.
• Syntax
• Semantics
• Logical inference = reasoning
Disadvantages of logic for knowledge
representation and processing
• Availability of nonmonotonic reasoning is
absent
• Impossibility of using of uncertainty and
working with fuzzy patterns and classes
• Necessity of formalization of knowledge
• Impossibility of working with several
hypothesis concurrently and with
argumentation
Positive role of logic in development of
science and mankind
• Logic promoted organization in social
behavior of people (laws, centralized
powerful states, diplomacy)
• Logic promoted proof and development of
mathematics as result
• Logic is a reason of appearance of digital
electronics and computers
Negative role of logic from point of
view of cognitive science
• Logic deals with exact and certain entities,
but can not deal with patterns from
sensors (images)
• So logic negates learning by classification
and clusterization
• Logic can to use only determined
formalized entities (symbols) by anybody
• So logic is hard structure and is unable to
develop without external anybody
Logic and creativity
• Inside in logic it is impossible to create any
new thing
• All entities used in logic are exist there
from her creation by external anybody
• All models of learning in logic assume only
transformation from any formalized
knowledge in logic
Role of logic in AI
• Logic was first implemented model of
thinking (reasoning) and promote further
development of AI
• Logic is basis of class of powerful logic
programming languages (Prolog,
Smalltalk, Lisp)
• Logic was any obstacle of development of
neural networks and other methods of soft
computing
Adaptation of logic to new challenges
of AI
• Modal logics as attempt to improve expressiveness of 1order logic (60-70th years)
• Fuzzy logic as attempt to include uncertainty to logic
(1965)
• Logical programming as tool for development of more
suitable knowledge representations for intelligent
systems (1982)
• Pseudo-physical logics as attempt to use fuzzy logic and
1-order logic to describe of real environment (80th years)
• Description logic is similar to pseudo-physical logics
• Now task is development of neural based system with
associative processing of knowledge and to obtain from
it logical behavior (“repeat evolution of human”). Here
logic will be no tool for development but template for
estimation
Submit a questions to discuss
• Logic is enemy of creativity and
understanding of environment
• Logic is tool for making of predictability
and standard of behavior