There exists a considerable body of work on epistemic logics for resource-bounded reasoners. In this paper, we concentrate on a less studied aspect of resource-bounded reasoning, namely, on the ascription of beliefs and inference rules by the agents to each other. We present a formal model of a system of bounded reasoners which reason about each other’s beliefs, and investigate the problem of belief ascription in a resource-bounded setting. We show that for agents whose computational resources and memory are bounded, (...) correct ascription of beliefs cannot be guaranteed, even in the limit. We propose a solution to the problem of correct belief ascription for feasible agents which involves ascribing reasoning strategies , or preferences on formulas, to other agents, and show that if a resource-bounded agent knows the reasoning strategy of another agent, then its ascription of beliefs to the other agent is correct in the limit. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Hume Studies Volume XXII, Number 1, April 1996, pp. 193-202 Why Hume Wasn't an Atheist: A Reply to Andre BERYL LOGAN In a recent issue of Hume Studies,1 Shane Andre argues that, as Hume's position on theism can be read primarily from Philo's position in the Dialogues Concerning Natural Religion, and since Philo's position in the Dialogues is one of "limited theism," Hume was also a "limited theist" and (...) therefore not an atheist. According to Andre, a "limited theist" is one like Epicurus, "who denied, not that the Gods exist, but that they intervene in human affairs" and, he continues, "...at least in philosophical circles, the term 'atheist' is generally restricted to people who disbelieve any form of theism, and this is the sense in which I propose to enquire whether Hume was an atheist" (142). Andre's claim then is that Hume is not an atheist in this latter sense, but is a limited theist in the former sense. This is shown in "three major objections to standard theism" in the Dialogues: those addressing the Argument from Design and the problem of evil, as well as the lack of debate on whether or not God exists. Philo's criticisms of the Argument from Design amount to the claim that, "not that there is no God, but that, if there is a God," empirical evidence cannot show that God has any of the traditional characteristics of wisdom, power or goodness. The "proper conclusion" of Philo's argument from evil does not concern God's existence, but establishes that God is "limited in some important respect." Philo's "limited theism" is expressed in his ambivalent attitude toward Cleanthes' Argument from Design in Part 12 ("that the cause or causes of order in the universe probably bear some remote analogy to human Beryl Logan is at the Department of Philosophy, Scarborough College, University of Toronto, 1265 Military Trail, Scarborough, Ontario MlC 1A4, Canada, email: logan@lake.'scar.utoronto.ca 194 Beryl Logan intelligence"). In sum, Philo and Cleanthes never debate God's existence, and they accept a limited Deity, therefore they hold positions of limited theism, therefore Philo is not an atheist. While I agree with Andre's conclusion that Hume is not an atheist, I will show in this paper first, that the interpretation which provides his means for arriving at this conclusion is not consistent with the text and faces a number of difficulties, and second, that the sense in which Hume is a limited theist has to do with the limitations of human reason and experience, and not with God's limited nature. My criticisms of Andre's position will be directed at three points in his argument: (1) his claim for Philo's theism based on Philo's lack of scepticism about God's existence; (2) what he regards to be the "proper conclusion" (153) to the problem of evil, as this directly influences his view of Philo's scepticism and the nature of the Deity; and (3) his view that Philo's theism is to be found in his acceptance of the Argument from Design (Philo's limited theism). My arguments will centre upon the "suspense of judgement," and where and how this.mental stance is used by Hume in the arguments of the Dialogues.2 Scepticism about God's Existence Andre claims that the arguments in the Dialogues are directed only to God's nature and do not address God's existence in spite of the fact that Cleanthes concludes his Argument from Design by claiming that the data in the world provide conclusive analogical support for the existence and (human-like) intelligence of the (traditional) Deity.3 Cleanthes' anthropomorphic Argument from Design purports to "prove" that the world has an intelligent divine designer just like machines have intelligent human designers and the only difference between the causes based on the effects is one of degree and not one of kind: the designer of the world is far grander than the designer of a computer because the world is more complex than a computer. I would urge, though, that Philo's scepticism is directed at both aspects of the Argument... (shrink)

We present a framework for verifying systems composed of heterogeneous reasoning agents, in which each agent may have differing knowledge and inferential capabilities, and where the resources each agent is prepared to commit to a goal (time, memory and communication bandwidth) are bounded. The framework allows us to investigate, for example, whether a goal can be achieved if a particular agent, perhaps possessing key information or inferential capabilities, is unable (or unwilling) to contribute more than a given portion of its (...) available computational resources or bandwidth to the problem. We present a novel temporal epistemic logic, BMCL-CTL , which allows us to describe a set of reasoning agents with bounds on time, memory and the number of messages they can exchange. The bounds on memory and communication are expressed as axioms in the logic. As an example, we show how to axiomatise a system of agents which reason using resolution and prove that the resulting logic is sound and complete. We then show how to encode a simple system of reasoning agents specified in BMCL-CTL in the description language of the Mocha model checker (Alur et al., Proceedings of the tenth international conference on computer-aided verification (CAV) , 1998), and verify that the agents can achieve a goal only if they are prepared to commit certain time, memory and communication resources. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Hume Studies Volume XXII, Number 1, April 1996, pp. 193-202 Why Hume Wasn't an Atheist: A Reply to Andre BERYL LOGAN In a recent issue of Hume Studies,1 Shane Andre argues that, as Hume's position on theism can be read primarily from Philo's position in the Dialogues Concerning Natural Religion, and since Philo's position in the Dialogues is one of "limited theism," Hume was also a "limited theist" and (...) therefore not an atheist. According to Andre, a "limited theist" is one like Epicurus, "who denied, not that the Gods exist, but that they intervene in human affairs" and, he continues, "...at least in philosophical circles, the term 'atheist' is generally restricted to people who disbelieve any form of theism, and this is the sense in which I propose to enquire whether Hume was an atheist" (142). Andre's claim then is that Hume is not an atheist in this latter sense, but is a limited theist in the former sense. This is shown in "three major objections to standard theism" in the Dialogues: those addressing the Argument from Design and the problem of evil, as well as the lack of debate on whether or not God exists. Philo's criticisms of the Argument from Design amount to the claim that, "not that there is no God, but that, if there is a God," empirical evidence cannot show that God has any of the traditional characteristics of wisdom, power or goodness. The "proper conclusion" of Philo's argument from evil does not concern God's existence, but establishes that God is "limited in some important respect." Philo's "limited theism" is expressed in his ambivalent attitude toward Cleanthes' Argument from Design in Part 12 ("that the cause or causes of order in the universe probably bear some remote analogy to human Beryl Logan is at the Department of Philosophy, Scarborough College, University of Toronto, 1265 Military Trail, Scarborough, Ontario MlC 1A4, Canada, email: logan@lake.'scar.utoronto.ca 194 Beryl Logan intelligence"). In sum, Philo and Cleanthes never debate God's existence, and they accept a limited Deity, therefore they hold positions of limited theism, therefore Philo is not an atheist. While I agree with Andre's conclusion that Hume is not an atheist, I will show in this paper first, that the interpretation which provides his means for arriving at this conclusion is not consistent with the text and faces a number of difficulties, and second, that the sense in which Hume is a limited theist has to do with the limitations of human reason and experience, and not with God's limited nature. My criticisms of Andre's position will be directed at three points in his argument: (1) his claim for Philo's theism based on Philo's lack of scepticism about God's existence; (2) what he regards to be the "proper conclusion" (153) to the problem of evil, as this directly influences his view of Philo's scepticism and the nature of the Deity; and (3) his view that Philo's theism is to be found in his acceptance of the Argument from Design (Philo's limited theism). My arguments will centre upon the "suspense of judgement," and where and how this.mental stance is used by Hume in the arguments of the Dialogues.2 Scepticism about God's Existence Andre claims that the arguments in the Dialogues are directed only to God's nature and do not address God's existence in spite of the fact that Cleanthes concludes his Argument from Design by claiming that the data in the world provide conclusive analogical support for the existence and (human-like) intelligence of the (traditional) Deity.3 Cleanthes' anthropomorphic Argument from Design purports to "prove" that the world has an intelligent divine designer just like machines have intelligent human designers and the only difference between the causes based on the effects is one of degree and not one of kind: the designer of the world is far grander than the designer of a computer because the world is more complex than a computer. I would urge, though, that Philo's scepticism is directed at both aspects of the Argument... (shrink)

The effective reasoning capability of an agent can be defined as its capability to infer, within a given space and time bound, facts that are logical consequences of its knowledge base. In this paper we show how to determine the effective reasoning capability of an agent with limited memory by encoding the agent as a transition system and automatically verifying whether a state where the agent believes a certain conclusion is reachable from the start state. We present experimental results using (...) the Model Based Planner (MBP) which illustrates how the length of the deduction varies for different memory sizes. (shrink)

Practical reasoners are resource-bounded—in particular they require time to derive consequences of their knowledge. Building on the Timed Reasoning Logics (TRL) framework introduced in [1], we show how to represent the time required by an agent to reach a given conclusion. TRL allows us to model the kinds of rule application and conflict resolution strategies commonly found in rule-based agents, and we show how the choice of strategy can influence the information an agent can take into account when making decisions (...) at a particular point in time. We prove general completeness and decidability results for TRL, and analyse the impact of communication in an example system consisting of two agents which use different conflict resolution strategies. (shrink)

We propose a framework for modelling situated resource-bounded agents. The framework is based on an objective ascription of intentional modalities and can be easily tailored to the system we want to model and the properties we wish to specify. As an elaboration of the framework, we introduce a logic, OBA, for describing the observations, beliefs, goals and actions of simple agents, and show that OBA is complete, decidable and has an efficient model checking procedure, allowing properties of agents specified in (...) OBA to be verified using standard theorem proving or model checking techniques. (shrink)

Agents which perform inferences on the basis of unreliable information need an ability to revise their beliefs if they discover an inconsistency. Such a belief revision algorithm ideally should be rational, should respect any preference ordering over the agent’s beliefs (removing less preferred beliefs where possible) and should be fast. However, while standard approaches to rational belief revision for classical reasoners allow preferences to be taken into account, they typically have quite high complexity. In this paper, we consider belief revision (...) for agents which reason in a simpler logic than full first-order logic, namely rule-based reasoners. We show that it is possible to define a contraction operation for rule-based reasoners, which we call McAllester contraction, which satisfies all the basic Alchourrón, Gärdenfors and Makinson (AGM) postulates for contraction (apart from the recovery postulate) and at the same time can be computed in polynomial time. We prove a representation theorem for McAllester contraction with respect to the basic AGM postulates (minus recovery), and two additional postulates. We then show that our contraction operation removes a set of beliefs which is least preferred, with respect to a natural interpretation of preference. Finally, we show how McAllester contraction can be used to define a revision operation which is also polynomial time, and prove a representation theorem for the revision operation. (shrink)

This collection of seminal essays on Kant's Prolegomena to Any Future Metaphysics provides the student of philosophy with an invaluable overview of the issues and problems raised by Kant. Starting with the Carus translation of Kant's work, the edition offers a substantive introduction, six papers never before published together, and a comprehensive bibliography. Special attention is paid to the relationship between Kant and David Hume, whose philosophical investigations, according to Kant's famous quote, first interrupted Kant's "dogmatic slumber.".

In this paper, I will focus on two sections of otherwise extensively studied Humean texts that have received little or no attention in the scholarly literature. A substantial part of Part 12 of the Dialogues Concerning Natural Religion and Section XI of An Enquiry Concerning Human Understanding—also written in dialogue form—are concerned with similar doctrines: that the prospect of a future state, or afterlife, acts as the motivating influence on our earthly moral behaviour.

In this paper, I will focus on two sections of otherwise extensively studied Humean texts that have received little or no attention in the scholarly literature. A substantial part of Part 12 of the Dialogues Concerning Natural Religion and Section XI of An Enquiry Concerning Human Understanding—also written in dialogue form—are concerned with similar doctrines: that the prospect of a future state, or afterlife, acts as the motivating influence on our earthly moral behaviour.

Food security and food self-sufficiency are important regional goals for the Southern African Development Coordination Conference (SADCC). In the long run, success in these areas would reduce the incidence of drought-related mass starvation and the epidemic of malnutrition and undernutrition that exists among some tribal groups. For food production to improve, the governments must commit themselves to increasing the access of peasant farmers to critical agricultural inputs. If they do not take proper action in this area of development planning, domestic (...) food production is likely to stagnate or decline. This study is a broad examination of the relationship between government expenditures on imported inputs and the performance of the domestic food subsector. Because much data on government spending and agricultural production in Africa are unavailable, and those in published form are of suspect validity, the study is undertaken largely as a conceptual overview. The empirical analyses are conducted, therefore, largely to provide a staging ground for the conceptual arguments. (shrink)

This collection of seminal essays on the _Prolegomena_ provides the student of philosophy with an invaluable overview of the issues and problems raised by Kant. Starting with the Carus translation of Kant's work, the edition offers a substantive new introduction, six papers never before published together and a comprehensive bibliography. Special attention is paid to the relationship between Kant and David Hume, whose philosophical investigations, according to Kant's famous quote, first interrupted Kant's 'dogmatic slumber'.

This collection of seminal essays on the _Prolegomena_ provides the student of philosophy with an invaluable overview of the issues and problems raised by Kant. Starting with the Carus translation of Kant's work, the edition offers a substantive new introduction, six papers never before published together and a comprehensive bibliography. Special attention is paid to the relationship between Kant and David Hume, whose philosophical investigations, according to Kant's famous quote, first interrupted Kant's 'dogmatic slumber'.

Very little scholarly attention has been devoted to Part 1 of Hume's Dialogues Concerning Natural Religion. This lack has been addressed recently by Tweyman, who argues for the importance of this part in understanding the positions defended by the characters in the remainder of the dialogue, in accordance with the types that Hume discusses in part 12 of the Enquiry concerning Human Understanding—Cleanthes is a philosophical dogmatist who requires the application of excessive skepticism by Philo to turn to the approved (...) position of mitigated skepticism, while Demea is and remains a religious dogmatist. In the present paper I will address the question of why the Dialogues continues beyond Part 1 in the face of the statement by Philo, who is generally considered to be Hume's spokesperson in the dialogue, that the inquiry being undertaken—the investigation into the nature of the Deity—is beyond human reason. (shrink)

Part guide and part spiritual journey, this visually stunning book celebrates America's statewide system of historic back country roads. It takes armchair travelers on a richly illustrated journey thorough the most beautiful landscapes of one of the nation's most geographically diverse states, and serves as a guide for those who decide to embark on an actual trip over these charming lanes. The project began when photographer Bob Rashid undertook a two year odyssey to preserve the remarkable sights along the 67 (...) official Rustic Roads in Wisconsin. Wisconsin's Rustic Roads, in the images of Rashid and the words of five of Wisconsin's most recognized and cherished authors, is a testiment to places where the efficiency of a road is not measured by its speed, nor its purpose necessarily defined by a destination, and which beckons the reader to linger. (shrink)