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Intransitivity and Future Generations: Debunking Parfit's Mere Addition Paradox
Journal of Applied Philosophy, Vol. 20, No. 2,Intransitivity 2003 and Future Generations 187 Intransitivity and Future Generations: Debunking Parfit’s Mere Addition Paradox KAI M. A. CHAN Duties to future persons contribute critically to many important contemporaneous ethical dilemmas, such as environmental protection, contraception, abortion, and population policy. Yet this area of ethics is mired in paradoxes. It appeared that any principle for dealing with future persons encountered Kavka’s paradox of future individuals, Parfit’s repugnant conclusion, or an indefensible asymmetry. In 1976, Singer proposed a utilitarian solution that seemed to avoid the above trio of obstacles, but Parfit so successfully demonstrated the unacceptability of this position that Singer abandoned it. Indeed, the apparently intransitivity of Singer’s solution contributed to Temkin’s argument that the notion of “all things considered better than” may be intransitive. In this paper, I demonstrate that a time-extended view of Singer’s solution avoids the intransitivity that allows Parfit’s mere addition paradox to lead to the repugnant conclusion. However, the heart of the mere addition paradox remains: the time-extended view still yields intransitive judgments. I discuss a general theory for dealing with intransitivity (Tran- sitivity by Transformation) that was inspired by Temkin’s sports analogy, and demonstrate that such a solution is more palatable than Temkin suspected. When a pair-wise comparison also requires consideration of a small number of relevant external alternatives, we can avoid intransitivity and the mere addition paradox without infinite comparisons or rejecting the Independence of Irrelevant Alternatives Principle. Disagreement regarding the nature and substance of our duties to future persons is widespread. -
False Dilemma Wikipedia Contents
False dilemma Wikipedia Contents 1 False dilemma 1 1.1 Examples ............................................... 1 1.1.1 Morton's fork ......................................... 1 1.1.2 False choice .......................................... 2 1.1.3 Black-and-white thinking ................................... 2 1.2 See also ................................................ 2 1.3 References ............................................... 3 1.4 External links ............................................. 3 2 Affirmative action 4 2.1 Origins ................................................. 4 2.2 Women ................................................ 4 2.3 Quotas ................................................. 5 2.4 National approaches .......................................... 5 2.4.1 Africa ............................................ 5 2.4.2 Asia .............................................. 7 2.4.3 Europe ............................................ 8 2.4.4 North America ........................................ 10 2.4.5 Oceania ............................................ 11 2.4.6 South America ........................................ 11 2.5 International organizations ...................................... 11 2.5.1 United Nations ........................................ 12 2.6 Support ................................................ 12 2.6.1 Polls .............................................. 12 2.7 Criticism ............................................... 12 2.7.1 Mismatching ......................................... 13 2.8 See also -
A Set of Solutions to Parfit's Problems
NOÛS 35:2 ~2001! 214–238 A Set of Solutions to Parfit’s Problems Stuart Rachels University of Alabama In Part Four of Reasons and Persons Derek Parfit searches for “Theory X,” a satisfactory account of well-being.1 Theories of well-being cover the utilitarian part of ethics but don’t claim to cover everything. They say nothing, for exam- ple, about rights or justice. Most of the theories Parfit considers remain neutral on what well-being consists in; his ingenious problems concern form rather than content. In the end, Parfit cannot find a theory that solves each of his problems. In this essay I propose a theory of well-being that may provide viable solu- tions. This theory is hedonic—couched in terms of pleasure—but solutions of the same form are available even if hedonic welfare is but one aspect of well-being. In Section 1, I lay out the “Quasi-Maximizing Theory” of hedonic well-being. I motivate the least intuitive part of the theory in Section 2. Then I consider Jes- per Ryberg’s objection to a similar theory. In Sections 4–6 I show how the theory purports to solve Parfit’s problems. If my arguments succeed, then the Quasi- Maximizing Theory is one of the few viable candidates for Theory X. 1. The Quasi-Maximizing Theory The Quasi-Maximizing Theory incorporates four principles. 1. The Conflation Principle: One state of affairs is hedonically better than an- other if and only if one person’s having all the experiences in the first would be hedonically better than one person’s having all the experiences in the second.2 The Conflation Principle sanctions translating multiperson comparisons into single person comparisons. -
Russell's Paradox in Appendix B of the Principles of Mathematics
HISTORY AND PHILOSOPHY OF LOGIC, 22 (2001), 13± 28 Russell’s Paradox in Appendix B of the Principles of Mathematics: Was Frege’s response adequate? Ke v i n C. Kl e m e n t Department of Philosophy, University of Massachusetts, Amherst, MA 01003, USA Received March 2000 In their correspondence in 1902 and 1903, after discussing the Russell paradox, Russell and Frege discussed the paradox of propositions considered informally in Appendix B of Russell’s Principles of Mathematics. It seems that the proposition, p, stating the logical product of the class w, namely, the class of all propositions stating the logical product of a class they are not in, is in w if and only if it is not. Frege believed that this paradox was avoided within his philosophy due to his distinction between sense (Sinn) and reference (Bedeutung). However, I show that while the paradox as Russell formulates it is ill-formed with Frege’s extant logical system, if Frege’s system is expanded to contain the commitments of his philosophy of language, an analogue of this paradox is formulable. This and other concerns in Fregean intensional logic are discussed, and it is discovered that Frege’s logical system, even without its naive class theory embodied in its infamous Basic Law V, leads to inconsistencies when the theory of sense and reference is axiomatized therein. 1. Introduction Russell’s letter to Frege from June of 1902 in which he related his discovery of the Russell paradox was a monumental event in the history of logic. However, in the ensuing correspondence between Russell and Frege, the Russell paradox was not the only antinomy discussed. -
Lecture 5. Zeno's Four Paradoxes of Motion
Lecture 5. Zeno's Four Paradoxes of Motion Science of infinity In Lecture 4, we mentioned that a conflict arose from the discovery of irrationals. The Greeks' rejection of irrational numbers was essentially part of a general rejection of the infinite process. In fact, until the late 19th century most mathematicians were reluctant to accept infinity. In his last observations on mathematics1, Hermann Weyl wrote: \Mathematics has been called the science of the infinite. Indeed, the mathematician invents finite constructions by which questions are decided that by their very nature refer to the infinite. That is his glory." Besides the conflict of irrational numbers, there were other conflicts about the infinite process, namely, Zeno's famous paradoxes of motion from around 450 B.C. Figure 5.1 Zeno of Citium Zeno's Paradoxes of motion Zeno (490 B.C. - 430 B.C.) was a Greek philosopher of southern Italy and a member of the Eleatic School founded by Parmenides2. We know little 1Axiomatic versus constructive procedures in mathematics, The Mathematical Intelligencer 7 (4) (1985), 10-17. 2Parmenides of Elea, early 5th century B.C., was an ancient Greek philosopher born in Elea, a Greek city on the southern coast of Italy. He was the founder of the Eleatic school of philosophy. For his picture, see Figure 2.3. 32 about Zeno other than Plato's assertion that he went to Athens to meet with Socrates when he was nearly 40 years old. Zeno was a Pythegorean. By a legend, he was killed by a tyrant of Elea whom he had plotted to depose. -
The Development of Mathematical Logic from Russell to Tarski: 1900–1935
The Development of Mathematical Logic from Russell to Tarski: 1900–1935 Paolo Mancosu Richard Zach Calixto Badesa The Development of Mathematical Logic from Russell to Tarski: 1900–1935 Paolo Mancosu (University of California, Berkeley) Richard Zach (University of Calgary) Calixto Badesa (Universitat de Barcelona) Final Draft—May 2004 To appear in: Leila Haaparanta, ed., The Development of Modern Logic. New York and Oxford: Oxford University Press, 2004 Contents Contents i Introduction 1 1 Itinerary I: Metatheoretical Properties of Axiomatic Systems 3 1.1 Introduction . 3 1.2 Peano’s school on the logical structure of theories . 4 1.3 Hilbert on axiomatization . 8 1.4 Completeness and categoricity in the work of Veblen and Huntington . 10 1.5 Truth in a structure . 12 2 Itinerary II: Bertrand Russell’s Mathematical Logic 15 2.1 From the Paris congress to the Principles of Mathematics 1900–1903 . 15 2.2 Russell and Poincar´e on predicativity . 19 2.3 On Denoting . 21 2.4 Russell’s ramified type theory . 22 2.5 The logic of Principia ......................... 25 2.6 Further developments . 26 3 Itinerary III: Zermelo’s Axiomatization of Set Theory and Re- lated Foundational Issues 29 3.1 The debate on the axiom of choice . 29 3.2 Zermelo’s axiomatization of set theory . 32 3.3 The discussion on the notion of “definit” . 35 3.4 Metatheoretical studies of Zermelo’s axiomatization . 38 4 Itinerary IV: The Theory of Relatives and Lowenheim’s¨ Theorem 41 4.1 Theory of relatives and model theory . 41 4.2 The logic of relatives . -
Reflexivity and Self-Referentiality 0.8Em in Inverse Monoids and Categories
Reflexivity and Self-Referentiality In Inverse Monoids and Categories Peter M. Hines York – Mathematics – 2019 www.peterhines.info Reflexivity and Self-Referentiality Some motivation ... This talk is about some inverse category theory closely associated with logic and theoretical computer science. The general topic is models of self-referentiality. We aim to: 1 Describe the historical context & importance. 2 Give concrete axioms & examples. 3 Do all this in the reversible (inverse monoid) setting. www.peterhines.info Reflexivity and Self-Referentiality Historical Context (I) — Foundations & Logic Scenes from the frog-mouse wars www.peterhines.info Reflexivity and Self-Referentiality The historical setting The late 19th and early to mid 20th century saw some- thing of a crisis in the foundations of mathematics. This can be compared to the controversy caused by the introduction of calculus that was resolved by rigorous no- tions of limit & convergence. However, it was more profound, and less easily resolved. Its aftermath is still relevant today. www.peterhines.info Reflexivity and Self-Referentiality The problems of infinity Georg Cantor lit the fuse, and stepped back to a safe distance ... His work was not always appreciated: A ”scientific charlatan”, a ”renegade” and a ”corrupter of youth” — Leopold Kroenecker Mathematics is ”ridden through and through with the per- nicious idioms of set theory”, which is ”utter nonsense” that is ”laughable” and ”wrong” — Ludwig Wittgenstein www.peterhines.info Reflexivity and Self-Referentiality A more balanced approach A very readable contemporaneous account: Mathematical Rigor, past and present – J. Pierpont (1928) The Mengenlehre of Cantor [Set Theory] has brought to light a number of paradoxes which have profoundly disturbed the mathematical community for a quarter of a century. -
Paradoxes Situations That Seems to Defy Intuition
Paradoxes Situations that seems to defy intuition PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Tue, 08 Jul 2014 07:26:17 UTC Contents Articles Introduction 1 Paradox 1 List of paradoxes 4 Paradoxical laughter 16 Decision theory 17 Abilene paradox 17 Chainstore paradox 19 Exchange paradox 22 Kavka's toxin puzzle 34 Necktie paradox 36 Economy 38 Allais paradox 38 Arrow's impossibility theorem 41 Bertrand paradox 52 Demographic-economic paradox 53 Dollar auction 56 Downs–Thomson paradox 57 Easterlin paradox 58 Ellsberg paradox 59 Green paradox 62 Icarus paradox 65 Jevons paradox 65 Leontief paradox 70 Lucas paradox 71 Metzler paradox 72 Paradox of thrift 73 Paradox of value 77 Productivity paradox 80 St. Petersburg paradox 85 Logic 92 All horses are the same color 92 Barbershop paradox 93 Carroll's paradox 96 Crocodile Dilemma 97 Drinker paradox 98 Infinite regress 101 Lottery paradox 102 Paradoxes of material implication 104 Raven paradox 107 Unexpected hanging paradox 119 What the Tortoise Said to Achilles 123 Mathematics 127 Accuracy paradox 127 Apportionment paradox 129 Banach–Tarski paradox 131 Berkson's paradox 139 Bertrand's box paradox 141 Bertrand paradox 146 Birthday problem 149 Borel–Kolmogorov paradox 163 Boy or Girl paradox 166 Burali-Forti paradox 172 Cantor's paradox 173 Coastline paradox 174 Cramer's paradox 178 Elevator paradox 179 False positive paradox 181 Gabriel's Horn 184 Galileo's paradox 187 Gambler's fallacy 188 Gödel's incompleteness theorems -
The Surprise Examination Or Unexpected Hanging Paradox Timothy Y
The Surprise Examination or Unexpected Hanging Paradox Timothy Y. Chow [As published in Amer. Math. Monthly 105 (1998), 41–51; ArXived with permission.] Many mathematicians have a dismissive attitude towards paradoxes. This is un fortunate, because many paradoxes are rich in content, having connections with serious mathematical ideas as well as having pedagogical value in teaching elementary logical reasoning. An excellent example is the socalled “surprise examination paradox” (de scribed below), which is an argument that seems at first to be too silly to deserve much attention. However, it has inspired an amazing variety of philosophical and mathemati cal investigations that have in turn uncovered links to Godel's¨ incompleteness theorems, game theory, and several other logical paradoxes (e.g., the liar paradox and the sorites paradox). Unfortunately, most mathematicians are unaware of this because most of the literature has been published in philosophy journals. In this article, I describe some of this work, emphasizing the ideas that are particularly interesting mathematically. I also try to dispel some of the confusion that surrounds the paradox and plagues even the published literature. However, I do not try to correct every error or explain every idea that has ever appeared in print. Readers who want more comprehensive surveys should see [30, chapters 7 and 8], [20], and [16]. At times I assume some knowledge of mathematical logic (such as may be found in Enderton [10]), but the reader who lacks this background may safely skim these sections. 1. The paradox and the metaparadox Let us begin by recalling the paradox. -
The Sorites Paradox
The sorites paradox phil 20229 Jeff Speaks April 17, 2008 1 Some examples of sorites-style arguments . 1 2 What words can be used in sorites-style arguments? . 3 3 Ways of solving the paradox . 3 1 Some examples of sorites-style arguments The paradox we're discussing today and next time is not a single argument, but a family of arguments. Here are some examples of this sort of argument: 1. Someone who is 7 feet in height is tall. 2. If someone who is 7 feet in height is tall, then someone 6'11.9" in height is tall. 3. If someone who is 6'11.9" in height is tall, then someone 6'11.8" in height is tall. ...... C. Someone who is 3' in height is tall. The `. ' stands for a long list of premises that we are not writing down; but the pattern makes it pretty clear what they would be. We could also, rather than giving a long list of premises `sum them up' with the following sorites premise: For any height h, if someone's height is h and he is tall, then someone whose height is h − 0:100 is also tall. This is a universal claim about all heights. Each of the premises 2, 3, . is an instance of this universal claim. Since universal claims imply their instances, each of premises 2, 3, . follows from the sorites premise. This is a paradox, since it looks like each of the premises is true, but the con- clusion is clearly false. Nonetheless, the reasoning certainly appears to be valid. -
Lecture 2.9: Russell's Paradox and the Halting Problem
Lecture 2.9: Russell's paradox and the halting problem Matthew Macauley Department of Mathematical Sciences Clemson University http://www.math.clemson.edu/~macaule/ Math 4190, Discrete Mathematical Structures M. Macauley (Clemson) Lecture 2.9: Russell's paradox & the halting problem Discrete Mathematical Structures 1 / 8 Russell's paradox Recall Russell's paradox: Suppose a town's barber shaves every man who doesn't shave himself. Who shaves the barber? This was due to British philosopher, logician, and mathematician Bertrand Russell (1872{1970), as an informal way to describe the paradox behind the set of all sets that don't contain themselves: S = fA j A is a set, and A 62 Ag: If such a set exists, then S 2 S −! S 62 S; S 62 S −! S 2 S; which is a contradiction. M. Macauley (Clemson) Lecture 2.9: Russell's paradox & the halting problem Discrete Mathematical Structures 2 / 8 A “fix” for Russell's paradox Let U be a universal set, and let S = fA j A ⊆ U and A 62 Ag: Now, suppose that S 2 S. Then by definition, S ⊆ U and S 62 S. If S 62 S, then :S ⊆ U ^ S 62 S =) S 6⊆ U _ S 2 S =) S 6⊆ U: In other words, there cannot exist a \set of all sets", but we can define a \class of all sets". One may ask whether we can always get rid of contradictions in this manner. In 1931, Kurt G¨odelsaid \no." G¨odel'sincompleteness theorem (informally) Every axiomatic system that is sufficient to develop the basic laws of arithmetic cannot be both consistent and complete. -
Discontinuous Particle Dynamics Beyond Relativity
From relativistic to quantum universe: Observation of a spatially- discontinuous particle dynamics beyond relativity Sergey A. Emelyanov Ioffe Institute, 194021 St. Petersburg, Russia Correspondence: [email protected] Abstract. We perform an experimental test where we directly observe light-induced electron transitions with a macroscopic spatial discontinuity. The effect is related to the fundamental indivisibility of macroscopic orbit-like quantum states reminiscent of so-called extended states in the integer quantum Hall system. The test has become realizable due to the discovering of a quantum phase with spontaneous pervasive quantum ordering reminiscent of that of a single atom. The observed transitions may be regarded as a peculiar quantum dynamics beyond relativity, which implies that the current relativistic model of universe should be replaced by a deeper quantum model. It is the Bohm’s model of undivided universe which now should involve a deeper-than-classical concept of absolute simultaneity and a deeper- than-relativistic concept of space and time. Ultimately, our test thus establishes a new hierarchy of fundamental physical theories where the de Broglie-Bohm realistic quantum theory is the deepest theory which does not contradict either classical physics or relativity but rather is beyond both. This is because the fact that quantum theory is dealing with a deeper reality where physical objects are not self-sufficient entities and therefore their discontinuous transitions are possible within an overall quantum system which may well be macroscopic. Keywords: atom-like macroscopic quantum ordering, spatially-discontinuous particle dynamics, Bohm’s undivided universe I. Introduction 1.1. The current view of the universe: why the Minkowski model of spacetime As it follows from the history of science, our view of universe is not unchangeable but determined by the physical theory which is regarded as being the most fundamental in a given historical period.