Opening the gate of verification: intellectual trends in the 17th century Arab-Islamic world

For much of the 20th century, it was widely assumed that early modern Arabic-Islamic civilisation had been in an advanced state of 'decadence' or 'sclerosis'. The 'golden' or 'classical' age of Arabic-Islamic civilisation had, it was believed, come to an end in the 13th or 14th century, giving way to a 'dark age' of intellectual stagnation - an age of 'imitation and compilation' - that lasted until the 19th century 'renaissance' (nahda). This sad intellectual state of affairs was also thought to mirror an imagined economic and demographic decline attributed to Ottoman (mis)rule and/or shifts in international trade routes

Meaning and definition:Skepticism and semantics in twelfth-century Arabic Philosophy

The theory of essential definitions is a fundamental anti-sceptic element of the Aristotelian-Avicennian epistemology. In this theory, when we distinguish the genus and the specific differentia of a given essence we thereby acquire a scientific understanding of it. The aim of this article is to analyse systematically the sceptical reasons, arguments and conclusions against real definitions of three major authorities of twelfth-century Arabic philosophy: Fahr al-Din al-Razi, Sihab al-Din al-Suhrawardi and Abu l-Barakat al-Badadi. I focus on showing how their refutation of our capacity to provide essential definitions of things is rooted in their semantic theory: we only know things under certain descriptions which are identical to the meanings of the words that we use to refer to them, yet these descriptions do not capture the essences of things in themselves. The best result one can achieve with Aristotelian-Avicennian scientific definitions is a "nominal definition". With this, Razi, Suhrawardi and Abu l-Barakat will put some serious epistemic limitations on our capacity to attain scientific knowledge of things, at least as Aristotle and Avicenna would have it

Data Dissemination in Wireless Sensor Networks with Network Coding

In wireless sensor networks (WSNs), it is often necessary to update the software running on sensors, which requires reliable dissemination of large data objects to each sensor with energy efficiency. During data dissemination, due to sleep scheduling designed for energy efficiency, some sensors may not receive some packets at some time slots. In the meantime, due to the unreliability of wireless communication, a sensor may not successfully receive a packet even when it is in the active mode. Thus, retransmission of such packets to those sensors is necessary, which consumes more energy and increases the delay of data dissemination cycle. In this paper, we propose a network coding-based approach in data dissemination such that data dissemination can be accomplished at the earliest time. Thus, less energy is consumed and the delay can be decreased. The impact of packet loss probability and the sleep probability of sensors on the network coding gain is analyzed. A threshold is also given to decide whether the current sleep scheduling is effective on energy saving in data dissemination process or not. Simulation results demonstrate the effectiveness and scalability of the proposed work