Ana Almeida

Parte do cinema brasileiro pensado e elaborado nos anos 2010 produziu gestos sintomáticos da corrida desenvolvimentista e imobiliária em grandes cidades brasileiras a partir de leituras temporais não-lineares. A partir de uma constelação de imagens acionadas por um grupo de cinco filmes, este artigo busca aproximar sequências a partir de três conceitos temporais distintos: a perspectiva ecobiótica andina de tempo, o tempo espiralar em rituais do Congado e o tempo Exu. Com eles, é possível percebemos parte do cinema brasileiro revelando, em suas cidades, a estrutura fóssil em projetos de futuro.

Vardanyan’s Theorems [36, 37] state that $\mathsf {QPL}(\mathsf {PA})$ —the quantified provability logic of Peano Arithmetic—is $\Pi ^0_2$ complete, and in particular that this already holds when the language is restricted to a single unary predicate. Moreover, Visser and de Jonge [38] generalized this result to conclude that it is impossible to computably axiomatize the quantified provability logic of a wide class of theories. However, the proof of this fact cannot be performed in a strictly positive signature. The system $\mathsf {QRC_1}$ was previously introduced by the authors [1] as a candidate first-order provability logic. Here we generalize the previously available Kripke soundness and completeness proofs, obtaining constant domain completeness. Then we show that $\mathsf {QRC_1}$ is indeed complete with respect to arithmetical semantics. This is achieved via a Solovay-type construction applied to constant domain Kripke models. As corollaries, we see that $\mathsf {QRC_1}$ is the strictly positive fragment of $\mathsf {QGL}$ and a fragment of $\mathsf {QPL}(\mathsf {PA})$.

In this guest column, the author argues against Wittgenstein's aphorism that the human body is the best picture of the human soul. Such a picture, she shows, would have to include all that a person is, in some sense, inseparable from. Drawing from Plato's analogy between city and soul, and from Socrates's description of a luxurious city, this piece argues that what we are inseparable from are mostly things and persons that our body can go on without. To the extent that such things and persons, and the relationship in which we stand to them, are distinct from our bodies, what we are inseparable from is also a sign that we are not self-sufficient creatures. Thus, the piece concludes, inseparability is evidence of the species' gregariousness, and the body is only one among many tokens of a person's soul.