In this paper I consider Kenneth Schaffner''s(1998) rendition of ''''developmentalism'''' from the point of viewof bacteriophage biology. I argue that the fact that a viablephage can be produced from purified DNA and host cellularcomponents lends some support to the anti-developmentalist, ifthey first show that one can draw a principled distinctionbetween genetic and environmental effects. The existence ofhost-controlled phage host range restriction supports thedevelopmentalist''s insistence on the parity of DNA andenvironment. However, in the case of bacteriophage, thedevelopmentalist stands on (...) less firm ground than when organismswith nervous systems, such as Schaffner''s C. elegans, areconsidered. (shrink)
Fitch's argument purports to show that if all truths are knowable then all truths are known. The argument exploits the fact that the knowledge predicate or operator is untyped and may thus apply to sentences containing itself. This article outlines a response to Fitch's argument based on the idea that knowledge is typed. The first part of the article outlines the philosophical motivation for the view, comparing it to the motivation behind typing truth. The second, formal part presents a (...) logic in which knowledge is typed and demonstrates that it allows nonlogical truths to be knowable yet unknown. (shrink)
This case for discussion highlights some of the ethical difficulties that may arise in the use of molecular typing techniques in the control of infectious diseases. Molecular typing techniques offer evidence (stronger than regular epidemiological exploration of sources and contacts) for claims about infection routes. Such evidence will mean that public health authorities need to think about how to respond ethically to causal responsibility for contagion. In this context, questions are raised about the use of molecular typing (...) methods for source and contact tracing in the control of infectious diseases. (shrink)
Next SectionPreimplantation tissue typing has been proposed as a method for creating a tissue matched child that can serve as a haematopoietic stem cell donor to save its sick sibling in need of a stem cell transplant. Despite recent promising results, many people have expressed their disapproval of this method. This paper addresses the main concerns of these critics: the risk of preimplantation genetic diagnosis (PGD) for the child to be born; the intention to have a donor child; the (...) limits that should be placed on what may be done to the donor child, and whether the intended recipient can be someone other than a sibling. The author will show that these concerns do not constitute a sufficient ground to forbid people to use this technique to save not only a sibling, but also any other loved one’s life. Finally, the author briefly deals with two alternative scenarios: the creation of a human leukocyte antigen (HLA) matched child as an insurance policy, and the banking of HLA matched embryos. (shrink)
This response to Rump and Woonink (2012) on ethical questions concerning the use of molecular typing techniques in the control of infectious diseases examines the use of typing in Canada and the legal framework that will govern its increasing use for source and contact tracing in provincial health systems. It examines whether current public health and privacy laws and constitutional protections provide the appropriate balance between public and individual interests in the control of infectious diseases.
One of the more controversial uses of preimplantation genetic diagnosis (PGD) involves selecting embryos with a specific tissue type so that the child to be born can act as a donor to an existing sibling who requires a haematopoietic stem cell transplant. PGD with HLA tissue typing is used to select embryos that are free of a familial genetic disease and that are also a tissue match for an existing sibling who requires a transplant. Preimplantation HLA tissue typing (...) occurs when parents select embryos that are not at risk of a familial genetic disease to be a match for an existing sibling who requires a transplant. In Victoria, Australia, applications to use PGD with HLA tissue typing are reviewed by the Infertility Treatment Authority on a case by case basis. Preimplantation HLA tissue typing is prohibited prima facie because the embryo to be tested would not be at risk for a genetic abnormality or disease. Arguments for or against the use of PGD/HLA tissue typing are based on several key issues including the commodification and welfare of the donor child. This essay aims to show that that the same arguments apply to both PGD with HLA tissue typing and Preimplantation HLA tissue typing, and that the policy distinction between the two procedures is therefore ethically inconsistent. (shrink)
We present Property Theory with Curry Typing (PTCT), an intensional first-order logic for natural language semantics. PTCT permits fine-grained specifications of meaning. It also supports polymorphic types and separation types. We develop an intensional number theory within PTCT in order to represent proportional generalized quantifiers like âmost.â We use the type system and our treatment of generalized quantifiers in natural language to construct a type-theoretic approach to pronominal anaphora that avoids some of the difficulties that undermine previous type-theoretic analyses (...) of this phenomenon. (shrink)
A BSTRACT. We present Property Theory with Curry Typing, an intensional ﬁrst-order logic for natural language semantics. PTCT permits ﬁne-grained speciﬁcations of meaning. It also supports polymorphic types and separation types.1 We develop an intensional number theory within PTCT in order to represent proportional generalized quantiﬁers like most. We use the type system and our treatment of generalized quantiﬁers in natural language to construct a typetheoretic approach to pronominal anaphora that avoids some of the difﬁculties that undermine previous type-theoretic (...) analyses of this phenomenon. (shrink)
The author draws on his own experience of helping to make and deliver public policy to indicate the wider context in which ethical decisions have to be made: the law, contested interpretations of the law which have to be settled in the courts, and wider political and economic factors. He argues that the concept of respect for the early embryo does have substance because of the strict regulatory regime of the Human Fertilisation and Embryology Authority (HFEA). He considers the arguments (...) that the early embryo ‘[e]njoys the full rights of the human being and should be accorded respect owed to a human being’. He concludes that these arguments are not finally convincing. He also looks at the moral status of the early embryo in Christian tradition and argues that perhaps from the fourth and certainly from the seventh century in the West until 1869, offences against the early embryo were regarded as less serious than offences against the embryo when developed further. For these reasons he concludes that there should be no absolute prohibition against research on an early embryo up to fourteen days. He also looks at recent cases involving pre-implantation diagnosis (PGD) and tissue typing with a view to obtaining matching tissue from an early embryo for a sibling suffering from a life-threatening disease. Although a distinction has been made between what might be licit in the case of a genetic disorder in the sibling but illicit if the disorder is not genetic, he argues that it could be in the best interests of the early embryo, the child that is to be, if in either case if it was selected with a view to matching the tissue of a sibling. (shrink)
One of the main aspects of a neurobiological theory of language is the problem of meaning (or semantic content) in the brain. A full explanation of meaning requires a combined approach to semantic typing and the semantic success of cerebral states or processes. Pulvermüller presents his Hebbian model of language in the brain (HML) as an account of semantic success. If his proposal turns out to be viable, however, it may also promote a theory of semantic typing.
The UK Human Fertilisation and Embryology Authority was right to permit tissue typing preimplantation genetic diagnosisOn July 21 2004, the Human Fertilisation and Embryology Authority , Britain’s regulatory agency for reproductive technologies, revised its policy on preimplantation genetic diagnosis for tissue typing.1,2 The authority of the HFEA to enact such a policy was affirmed by the UK’s highest court, the House of Lords, on April 28 2005.3 Preimplantation genetic diagnosis combines in vitro fertilisation with genetic testing. In PGD, (...) embryos generally undergo biopsy prior to the eight cell stage, followed by genetic testing for a particular trait. Tissue typing PGD is done to identify an embryo that is tissue matched for a child suffering from a severe disease requiring bone marrow or cord blood stem cell transplantation and for whom no living donor exists. This procedure was first performed in 2000.4 Precise matching of tissue types is critical to successful tissue transplant, and the donors of such tissues are often referred to as “saviour siblings”.Where a tissue matched individual already exists, extracting bone marrow from that individual or collecting cord blood already in storage, rather than creating a match, presents the most immediate treatment alternative. Bone marrow donation from adults or other medically competent individuals is not generally ethically contested, and bone marrow donation from medically incompetent individuals is also permissible under certain conditions.5 Where no living tissue donor exists, however, intentionally creating a donor through tissue typing PGD is among a short list of possible treatment options.The July HFEA policy change makes PGD licensable in cases where tissue typing is the only purpose of testing. Previously, PGD was licensable in the UK only for disease testing, and tissue typing PGD was permissible only when …. (shrink)
Guided by the work of William Alston, Jonathan Adler and Michael Levin propose a solution to the generality problem for reliabilism. In some respects their proposal improves on those we have discussed. We argue that the problem remains unsolved.
The Australian scientist Frank Macfarlane Burnet—winner of the Nobel Prize in 1960 for his contributions to the understanding of immunological tolerance—is perhaps best recognized as one of the formulators of the clonal selection theory of antibody production, widely regarded as the ‘central dogma’ of modern immunology. His work in studies in animal virology, particularly the influenza virus, and rickettsial diseases is also well known. Somewhat less known and publicized is Burnet’s research on bacteriophages, which he conducted in the first decade (...) of his research career, immediately after completing medical school. For his part, Burnet made valuable contributions to the understanding of the nature of bacteriophages, a matter of considerable debate at the time he began his work. Reciprocally, it was while working on the phages that Burnet developed the scientific styles, the habits of mind and laboratory techniques and practices that characterized him for the rest of his career. Using evidence from Burnet’s published work, as well as personal papers from the period he worked on the phages, this paper demonstrates the direct impact that his experiments with phages had on the development of his characteristic scientific style and approaches, which manifested themselves in his later career and theories, and especially in his thinking regarding various immunological problems. (shrink)
We study Artemov’s Reflective Combinatory Logic . We provide the explicit definition of types for and prove that every well-formed term has a unique type. We establish that the typability testing and detailed type restoration can be done in polynomial time and that the derivability relation for is decidable and PSPACE-complete. These results also formalize the intended semantics of the type t:F in . Terms store the complete information about the judgment “t is a term of type F”, and this (...) information can be extracted by the type restoration algorithm. (shrink)
The ecology movement has recently attempted to reinvigorate the image of Earth in terms of Lovelock and Epton’s “Gaia hypothesis.” I analyze the shortcomings of using Gaia imagery in the works of Lovelock, deep ecologists, feminists, and ecological poets, and conclude that while the hypothesis serves to alter consciousness, naming it Gaia reinforces the oppressive hierarchical patterns of patriarchal gender stereotypes that it opposes. We are moving toward a new paradigm of nonpatriarchal pluralistic co-evolution, but if deep ecology is going (...) to promote fully its development, it needs to recast or cast aside Gaia imagery. (shrink)
It was observed by Curry that when λ-terms can be assigned types, for example, simple types, these terms have nice properties . Coppo, Dezani, and Veneri, introduced type systems using conjunctive types, and showed that several important classes of terms can be characterized according to the shape of the types that can be assigned to these terms. For example, the strongly normalizable terms, the normalizable terms, and the terms having head-normal forms, can be characterized in some systems and Ω. The (...) proofs use variants of the method of reducibility. In this paper, we present a uniform approach for proving several meta-theorems relating properties of λ-terms and their typability in the systems and Ω. Our proofs use a new and more modular version of the reducibility method. As an application of our metatheorems, we show how the characterizations obtained by Coppo, Dezani, Veneri, and Pottinger, can be easily rederived. We also characterize the terms that have weak head-normal forms, which appears to be new. We conclude by stating a number of challenging open problems regarding possible generalizations of the realizability method. (shrink)
This paper studies intersection and union type assignment for the calculus , a proof-term syntax for Gentzen’s classical sequent calculus, with the aim of defining a type-based semantics, via setting up a system that is closed under conversion. We will start by investigating what the minimal requirements are for a system, for to be complete ; this coincides with System , the notion defined in Dougherty et al. ; however, we show that this system is not sound , so our (...) goal cannot be achieved. We will then show that System is also not complete, but can recover from this by presenting System as an extension of and showing that it satisfies completeness; it still lacks soundness. We show how to restrict so that it satisfies soundness as well by limiting the applicability of certain type assignment rules, but only when limiting reduction to call-by-name or call-by-value reduction; in restricting the system this way, we sacrifice completeness. These results when combined show that, with respect to full reduction, it is not possible to define a sound and complete intersection and union type assignment system for. (shrink)