Ethics are, of course, a fundamental part of professional practice. There are different philosophical schools of thought relating to ethics and, although there are often degrees of overlap, they are characterized more by difference than harmony. Among these philosophical schools, one school that has received relatively little attention in the professional literature (and a waning level of interest in the philosophical literature) is that of existentialism. This article outlines some of the main points of ethical theory in the works of (...) Friedrich Nietzsche, one of the founders of existentialist thought, and Jean-Paul Sartre, the best known of the existentialist thinkers, as well as other contributors to existentialist thought. Possible developments in existentialist ethical theory since the time of Sartre are also sketched out, and these are linked to contemporary social work concerns. (shrink)

A further reformulation of naïve set comprehension related to that proposed in _‘_Resolving Insolubilia: Internal Inconsistency and the Reform of Naive Set Comprehension’_ _ is possible in which contradiction is averted not by excluding sets such as the Russell Set but rather by treating sentences resulting from instantiation of such sets as the Russell Set in their own descriptions as invalid. So the set of all sets that are not members of themselves in this further revision is a valid set (...) but the claim that that set is or is not a member of itself is not validly expressible. Such an approach to set comprehension results in a set ontology co-extensive with that permitted by the Naïve Set Comprehension Principle itself. This approach has as strong a claim to consistency as that formulated in _‘_Resolving Insolubilia: Internal Inconsistency and the Reform of Naive Set Comprehension’. (shrink)

A further reformulation of Naive Set Comprehension related to that proposed in “Resolving Insolubilia: Internal Inconsistency and the Reform of Naive Set Comprehension” is possible in which contradiction is averted not by excluding sets such as the Russell Set but rather by treating sentences resulting from instantiation of such sets as the Russell Set in their own descriptions as invalid. So the set of all sets that are not members of themselves in this further revision is a valid set but (...) the claim that that set is or is not a member of itself is not validly expressible. Such an approach to set comprehension results in a set ontology co-extensive with that permitted by the Naive Set Comprehension Principle itself. This approach has as strong a claim to consistency as that formulated in “Resolving Insolubilia: Internal Inconsistency and the Reform of Naive Set Comprehension.”. (shrink)

If the concept of proof (including arithmetic proof) is syntactically restricted to closed sentences (or their Gödel numbers), then the standard accounts of Gödel’s Incompleteness Theorems (and Löb’s Theorem) are blocked. In these standard accounts (Gödel’s own paper and the exposition in Boolos’ Computability and Logic are treated as exemplars), it is assumed that certain formulas (notably so called “Gödel sentences”) containing the Gödel number of an open sentence and an arithmetic proof predicate are closed sentences. Ordinary usage of the (...) term “provable” (and indeed “unprovable”) favors their restriction to closed sentences which unlike so-called open sentences can be true or false. In this paper the restricted form of provability is called strong provability or unprovability. If this concept of proof is adopted, then there is no obvious alternative path to establishing those theorems. (shrink)