Universal algebra uniformly captures various algebraic structures, by expressing them as equational theories or abstract clones. The ubiquity of algebraic structures in mathematics and related fields has given rise to several variants of universal algebra, such as theories of symmetric operads, non-symmetric operads, generalised operads, PROPs, PROs, and monads. These variants of universal algebra are called notions of algebraic theory. In this paper, we develop a unified framework for them. The key observation is that each notion of algebraic theory can be identified with a monoidal category, in such a way that algebraic theories correspond to monoid objects therein.

En este artículo presentaremos primero dos discusiones muy puntuales que confrontan a Badiou con Nancy y Lacan en torno al vacío y al infinito. Mostraremos después cómo pensamos que se articula el concepto, tanto en filosofía como en psicoanálisis, a la luz de dichas complejidades y de las imbricadas relaciones entre los diversos dispositivos de pensamiento que ellas implican.

We discuss views about whether the universe can be rationally comprehended, starting with Plato, then Leibniz, and then the views of some distinguished scientists of the previous century. Based on this, we defend the thesis that comprehension is compression, i.e., explaining many facts using few theoretical assumptions, and that a theory may be viewed as a computer program for calculating observations. This provides motivation for defining the complexity of something to be the size of the simplest theory for it, in other words, the size of the smallest program for calculating it. This is the central idea of algorithmic information theory (AIT), a field of theoretical computer science.

The broad concept of an individual’s welfare is actually a cluster of related specific concepts that bear a “family resemblance” to one another. One might care about how a policy will affect people both in terms of their subjective preferences and also in terms of some notion of their objective interests. This paper provides a framework for evaluation of policies in terms of welfare criteria that combine these two considerations. Sufficient conditions are provided for such a criterion to imply the same ranking of social states as does Pareto’s unanimity criterion. Sufficiency is proved via study of a community of agents with interdependent ordinal preferences.

Aristóteles es mucho Aristóteles. El tratado Peri psyché es la primera gran sistematización sobre el alma que ha llegado hasta nosotros. Así, ni más ni menos. Estamos ante una obra que se presenta como un hueso duro de roer. El Estagirita pone toda la carne en el asador y con su contundente y fundamental terminología analiza meticulosamente los atributos del alma. Con los conceptos de sustancia/accidente, materia/forma y potencia/acto, el Estagirita estudia la dualidad cuerpo/alma. Si la Física era una ontología del movimiento, Peri psychées una ontología del alma.

This paper gives a thorough critique of the foundations of quantum physics in its mainstream interpretation (i.e., treating pure states as primitives, without reference to hidden variables, and without modifications of the quantum laws). This is achieved by cleanly separating a concise version of the (universally accepted) formal core of quantum physics from the (controversial) interpretation issues. The latter are primarily related to measurement, but also to questions of existence and of the meaning of basic concepts like ‘state’ and ‘particle’. The requirements for good foundations of quantum physics are discussed.

En las páginas que siguen vamos a ofrecer, como lo anuncia el título del presente trabajo, unas notas que puedan servir de reexposición de la Teoría de la Esencia como «esencia genérica» o «procesual» que Gustavo Bueno ha venido presentando en El Animal Divino y en otros lugares de su obra. Entendemos desde el Materialismo Filosófico por «esencia genérica» a aquellas estructuras holóticas que conforman totalidades sistemáticas{5} (géneros, especies) tales que ellas mismas no se expresan sino a través del desarrollo procesual de sus partes componentes incluso cuando el despliegue de tales partes –de suyo muy heterogéneas y hasta opuestas entre sí– dan lugar a fases dialécticas en las que la propia esencia queda por así decir «desecha», «negada» en virtud de los resultados mismos que arroja el curso de su transformación.

This is a brief introduction to the life and ideas of the Lithuanian-German physicist, philosopher and religious thinker Max B. Weinstein, who is today best known for his thoughts concerning so-called pandeism. An accomplished theoretical physicist and characteristic figure in the fin-de-siecle transition of the physical world view, Weinstein contributed to a wide range of physics. He was an early if not unsympathetic critic of Einstein’s theory of relativity and Minkowski’s formulation of it. In this respect he was unoriginal, but in the broader context of science and humanist culture he was an original thinker.

A partir de Sylvan [1990] y Urbas [1996] demostramos la heterodoxia de las lógicas de da Costa. Probamos que estas lógicas no satisfacen el teorema de sustitución. Más aún, probamos que no existen extensiones más débiles que la lógica clásica y más fuerte que las lógicas de da Costa las cuales satisfagan el teorema de sustitución.

We study the informational underpinnings of thermodynamics and statistical mechanics, using an abstract framework, general probabilistic theories, capable of describing arbitrary physical theories. This allows one to abstract the informational content of a theory from the concrete details of its formalism. In this framework, we extend the treatment of microcanonical thermodynamics, namely the thermodynamics of systems with a well-defined energy, beyond the known cases of classical and quantum theory, formulating two necessary requirements for a well-defined thermodynamics. We adopt the recent approach of resource theories, where one studies the transitions between states that can be accomplished with a restricted set of physical operations. We formulate three different resource theories, differing in the choice of the restricted set of physical operations. To bridge the gap between the objective dynamics of particles and the subjective world of probabilities, one of the core issues in the foundations of statistical mechanics, we propose four information-theoretic axioms.