84 research outputs found
A note on drastic product logic
The drastic product is known to be the smallest -norm, since whenever . This -norm is not left-continuous, and hence it
does not admit a residuum. So, there are no drastic product -norm based
many-valued logics, in the sense of [EG01]. However, if we renounce standard
completeness, we can study the logic whose semantics is provided by those MTL
chains whose monoidal operation is the drastic product. This logic is called
in [NOG06]. In this note we justify the study of this
logic, which we rechristen DP (for drastic product), by means of some
interesting properties relating DP and its algebraic semantics to a weakened
law of excluded middle, to the projection operator and to
discriminator varieties. We shall show that the category of finite DP-algebras
is dually equivalent to a category whose objects are multisets of finite
chains. This duality allows us to classify all axiomatic extensions of DP, and
to compute the free finitely generated DP-algebras.Comment: 11 pages, 3 figure
Expanding FLew with a Boolean connective
We expand FLew with a unary connective whose algebraic counterpart is the
operation that gives the greatest complemented element below a given argument.
We prove that the expanded logic is conservative and has the Finite Model
Property. We also prove that the corresponding expansion of the class of
residuated lattices is an equational class.Comment: 15 pages, 4 figures in Soft Computing, published online 23 July 201
A logical approach to fuzzy truth hedges
The starting point of this paper are the works of Hájek and Vychodil on the axiomatization of truth-stressing and-depressing hedges as expansions of Hájek's BL logic by new unary connectives. They showed that their logics are chain-complete, but standard completeness was only proved for the expansions over Gödel logic. We propose weaker axiomatizations over an arbitrary core fuzzy logic which have two main advantages: (i) they preserve the standard completeness properties of the original logic and (ii) any subdiagonal (resp. superdiagonal) non-decreasing function on [0, 1] preserving 0 and 1 is a sound interpretation of the truth-stresser (resp. depresser) connectives. Hence, these logics accommodate most of the truth hedge functions used in the literature about of fuzzy logic in a broader sense. © 2013 Elsevier Inc. All rights reserved.The authors acknowledge partial support of the MICINN projects TASSAT (TIN2010-20967-C04-01) and ARINF (TIN2009-14704-C03-03), and the FP7-PEOPLE-2009-IRSES project MaToMUVI (PIRSES-GA-2009-247584). Carles Noguera also acknowledges support of the research contract “Juan de la Cierva” JCI-2009-05453.Peer Reviewe
On some axiomatic extensions of the monoidal T-norm based logic MTL : an analysis in the propositional and in the first-order case
The scientific area this book belongs to are many-valued logics: in particular, the logic MTL and some of its extensions, in the propositional and in the first-order case. The book is divided in two parts: in the first one the necessary background about these logics, with some minor new results, are presented. The second part is devoted to more specific topics: there are five chapters, each one about a different problem. In chapter 6 a temporal semantics for Basic Logic BL is presented. In chapter 7 we move to first-order logics, by studying the supersoundness property: we have improved some previous works about this theme, by expanding the analysis to many extensions of the first-order version of MTL. Chapter 8 is dedicated to four different families of n-contractive axiomatic extensions of BL, analyzed in the propositional and in the first-order case: completeness, computational and arithmetical complexity, amalgamation and interpolation properties are studied. Finally, chapters 9 and 10 are about Nilpotent Minimum logic: in chapter 9 the sets of tautologies of some NM-chains (subalgebras of [0,1]_NM) are studied, compared and the problems of axiomatization and undecidability are tackled. Chapter 10, instead, concerns some logical and algebraic properties of (propositional) Nilpotent Minimum logic. The results (or an extended version of them) of these last chapters have been also presented in papers
ON SOME AXIOMATIC EXTENSIONS OF THE MONOIDAL T-NORM BASED LOGIC MTL: AN ANALYSIS IN THE PROPOSITIONAL AND IN THE FIRST-ORDER CASE
The scientific area this thesis belongs to are many-valued logics: in particular, the logic MTL and some of its extensions, in the propositional and in the first-order case (see [8],[9],[6],[7]). The thesis is divided in two parts: in the first one the necessary background about these logics,
with some minor new results, are presented. The second part is devoted to more specific topics: there are five chapters, each one about a different problem. In chapter 6 a temporal semantics for Basic Logic BL is
presented. In chapter 7 we move to first-order logics, by studying the supersoundness property: we have improved some previous works about this theme, by expanding the analysis to many extensions of the first-order version of MTL. Chapter 8 is dedicated to four different families of n-contractive axiomatic extensions of BL, analyzed in the propositional and in the first-order case: completeness, computational and arithmetical complexity, amalgamation and interpolation properties are studied. Finally, chapters 9 and 10 are about Nilpotent Minimum logic (NM, see [8]): in chapter 9 the sets of tautologies of some NM-chains (subalgebras
of [0,1]_NM) are studied, compared and the problems of axiomatization and undecidability are tackled. Chapter 10, instead, concerns some logical and algebraic properties of (propositional) Nilpotent Minimum logic. The results (or an extended version of them) of these last chapters have
been also presented in papers [1, 4, 5, 2, 3]. ---------------------------------References---------------------------------------------
[1] S. Aguzzoli, M. Bianchi, and V. Marra. A temporal semantics for Basic
Logic. Studia Logica, 92(2), 147-162, 2009. doi:10.1007/s11225-009-9192-3.
[2] M. Bianchi. First-order Nilpotent Minimum Logics: first steps. Submitted
for publication,2010.
[3] M. Bianchi. On some logical and algebraic properties of Nilpotent Minimum
logic and its relation with G\uf6del logic. Submitted for publication, 2010. [4] M. Bianchi and F. Montagna. Supersound many-valued logics and
Dedekind-MacNeille completions. Arch. Math. Log., 48(8), 719-736, 2009.
doi:10.1007/s00153-009-0145-3.
[5] M. Bianchi and F. Montagna. n-contractive BL-logics. Arch. Math. Log.,
2010. doi:10.1007/s00153-010-0213-8.
[6] P. Cintula, F. Esteva, J. Gispert, L. Godo, F. Montagna, and C. Noguera.
Distinguished algebraic semantics for t-norm based fuzzy logics: methods
and algebraic equivalencies. Ann. Pure Appl. Log., 160(1), 53-81, 2009.
doi:10.1016/j.apal.2009.01.012.
[7] P. Cintula and P. H\ue1jek. Triangular norm predicate fuzzy logics. Fuzzy Sets
Syst., 161(3), 311-346, 2010. doi:10.1016/j.fss.2009.09.006.
[8] F. Esteva and L. Godo. Monoidal t-norm based logic: Towards a
logic for left-continuous t-norms. Fuzzy sets Syst., 124(3), 271-288, 2001.
doi:10.1016/S0165-0114(01)00098-7.
[9] P. H\ue1jek. Metamathematics of Fuzzy Logic, volume 4 of Trends
in Logic. Kluwer Academic Publishers, paperback edition, 1998.
ISBN:9781402003707
The General Apple Property and Boolean terms in Integral Bounded Residuated Lattice-ordered Commutative Monoids
In this paper we give equational presentations of the varieties of {\em
integral bounded residuated lattice-ordered commutative monoids} (bounded
residuated lattices for short) satisfying the \emph{General Apple Property}
(GAP), that is, varieties in which all of its directly indecomposable members
are local. This characterization is given by means of Boolean terms: \emph{A
variety of \brl s has GAP iff there is an unary term such
that satisfies the equations and
, for some }. Using this
characterization, we show that for any variety of bounded
residuated lattice satisfying GAP there is such that the equation
holds in , that is, . As a consequence we improve Theorem 5.7 of
\cite{CT12}, showing in theorem that a\emph{ variety of \brls\ has Boolean
retraction term if and only if there is such that it satisfies the
equation .} We also see that in Bounded
residuated lattices GAP is equivalent to Boolean lifting property (BLP) and so,
it is equivalent to quasi-local property (in the sense of \cite{GLM12}).
Finally, we prove that a variety of \brl s has GAP and its semisimple members
form a variety if and only if there exists an unary term which is
simultaneously Boolean and radical for this variety.Comment: 25 pages, 1 figure, 2 table
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