the iranian civil code has limited the effects of unknown condition to nullification of such condition provided that it results in ignorance with respect to consideration. the code conveys no explicit provision concerning the effect of such condition not resulting in the ignorance. unknown condition refers to a condition on which there is not complete and comprehensive knowledge. this article l...

In formal systems that reason about knowledge, inferring that an agent actually does not know a particular fact can be problematic. Collins [l] has shown that there are many different modes of reasoning that a subject can use to show that he is ignorant of something; some of these, for example, involve the subject reasoning about the limitations of his own information-gathering and memory abili...

In this paper, we consider the coherent theory of (epistemic) uncertainty of Walley, in which beliefs are represented through sets of probability distributions, and we focus on the problem of modeling prior ignorance about a categorical random variable. In this setting, it is a known result that a state of prior ignorance is not compatible with learning. To overcome this problem, another state ...

'Even the wisest of doctors are relying on scientific truths the errors of which will be recognised within a few years time,' wrote Marcel Proust a century ago. At that time most people understood the severe limitations of medicine, but today doctors are viewed as having enormous power. Medical research is seen by the public as the 'most scientific' form of scientific research (1); television p...

If one looks at the history of mathematics, one sees periods of bursting creativity, when new ideas are being developed in a competitive and therefore very hasty spirit; and periods when people find that the ideas so recently in vogue are inexact, incoherent, possibly inconsistent; in such periods there is an urge to consolidate past achievements. I said " the history of mathematics " : but mat...

Engineers and scientists are increasingly required to design, test, and validate new complex systems in simulation environments and/or with limited experimental results due to international Epistemic Uncertainty Workshop, Sandia National Laboratories, Albuquerque, NM, August 6-7, 2002 © Ayyub 2002 2 and/or budgetary restrictions. Dealing with complex systems requires assessing knowledge and inf...

Recently Oaksford and Hahn (2004) proposed a Bayesian reconstruction of a classic argumentation fallacy Locke’s ‘argument from ignorance.’ Here this account is extended to what is probably the most well-known of all argumentation fallacies: circular reasoning or ‘begging the question’. A Bayesian analysis is shown to clarify when and where circular reasoning is good or bad, and how seeming para...