Monday, July 28, 2014

INTRODUCTION TO LOGIC


 . . this we do affirm—that if truth is to be sought in every division of Philosophy, we must, before all else, possess trustworthy principles and methods for the discernment of truth. Now the Logical branch is that which includes the theory of criteria and of proofs; so it is with this that we ought to make our beginnings.
—Sextus Empiricus

. . . bad reasoning as well as good reasoning is possible; and this fact is the foundation of the practical side of logic.
—Charles Sanders Peirce

What is logic?
Logic is the study of the methods and principles used to distinguish good (correct) from bad (incorrect) reasoning. 

traditional part of the study of logic has been the examination and analysis of falacies, which are common and often quite "natural" mistakes in reasoning. 

study of logic will give students techniques and methods for testing the correctness of many different kinds of reasoning
Logic has frequently been defined as the science of the laws of thought.
All reasoning is thinking, but not all thinking is reasoning

Premisses and Conclusions
Inference is a process by which one proposition is arrived at and affirmed on the basis of one or more other propositions accepted as the starting point of the process are either true or false, and in this they differ from questions, commands, and exclamations. 
We use the term "proposition" to refer to what such sentences as these are typically uttered to assert
 Corresponding to every possible inference is an argument, and it is with arguments that logic is chiefly concerned.



What do you value in life?


What Is Philosophy?


It is very difficult to give a satisfactory formal definition of philosophy. For philosophy is like those other great human enterprises of ideal society—art, science, and religion: every definition turns out to be the expression of an individual and limited conception, reflecting the practice of that enterprise in the definer's own culture, and shutting out as much as it includes. And no definition conveys much illumination apart from a knowledge of the concrete philosophies men have formulated, the philosophical problems out of which those formulations have grown, and the role which philosophical thinking has played in their own lives and in that of their culture. Philosophy, in other words, is a human and cultural enterprise to be inquired into, rather than a mere term to be defined. Any definition must emerge from a careful analysis of what men have been doing when they philosophized, and how that is to be distinguished from what they do when they engage in their other cultural enterprises. The boundaries between these different pursuits are notoriously vague; and different definitions reflect a more or less arbitrary drawing of the lines.

Philosophy and Religion, Science, and Art. Philosophical thinking, indeed, has very close relations with religion, with science, and with art. It has normally culminated in the attempt to do intellectually what religion has always done practically and emotionally: to establish human life in some satisfying and meaningful relation to the universe in which man finds himself, and to afford some wisdom in the conduct of human affairs. Historically, philosophy arose as the reflective criticism of religious and moral beliefs, and it has never ceased to have that critical concern. But in its methods it has been allied rather with science, even when it has been most critical of the scientific assumptions and conclusions prevailing at a given time. Philosophic and scientific thinking, in fact, were born together; and again and again philosophic reflection has been revitalized by fresh contact with the concepts, methods, and standards of scientific inquiry. And finally, those compre­hensive visions of the world and of human destiny which we cherish as the great philosophic systems of speculative thought are surely among the most imposing artistic achievements of the spirit of man. The outstanding philosophers, indeed, have been endowed with something of poetic imagination, critical acumen, natural piety, and spiritual insight.

So closely allied has philosophic thinking been with all the other basic cultural institutions of human society that we often call the general intellectual temper of an age—its pervasive world-outlook, its distinctive methods of thinking, its unques­tioned assumptions and climate of opinion— "the philosophy" of that period. But this usage hardly suffices to define the func­tion of philosophic thinking itself; that is both more self- conscious and more critically analytic than this would suggest. In every age there are men who, aware of this distinctive in­tellectual temper, either give it systematic expression or seek to modify certain of its aspects. It is they who carry on actual philosophic thinking and merit the title of "philosophers," be­cause they are concerned with the conscious analysis of meth­ods of thinking, and with the conscious formulation of a world outlook.

Philosophy: Paradox and Discovery

The term philosophy derives from the Greek words philein, to love or desire, and sophia, wisdom. Literally speaking, then, a philosopher is a "lover of wisdom." Hut what exactly does a lover of wisdom do? To answer this let us reflect on the process of social conditioning that all human beings undergo, the process that social scientists call enculturation. This is the systematic and efficient shaping— by family, peers, teachers, media, advertising, religion, music, government, and other forces—that turns a person into a functioning member of his or her society.

When a baby is born, it is neither a Hindu nor a Christian nor a Baha'i; it seeks inspiration and guidance in neither the Bible nor the Koran nor the Bhagavad Gita; it esteems neither Buddha nor Jesus nor Mohammed; it prefers nei­ther democracy nor dictatorship; it speaks neither Arabic nor French nor English; it prefers no particular mode of dress or hairstyle; it has a penchant neither for ice hockey nor football nor polo; it lip-syncs the vocals of neither Eminem nor Shania Twain nor Whitney Houston; it harbors no view on when, if ever, society may incarcerate a citizen; and it offers no opinions on the pro­priety of human cloning, whether human choices are free, whether humans should eat other species of animals, whether a dying person may hasten death, when (if ever) violence against others is justified, whether a clitoridectomy should be performed on a prepubescent girl, or where government should form the line between prudent security measures and overzealous infringe­ment of liberties. As the baby becomes a child, the child an adolescent, and the adolescent an adult, a systematic and efficient shaping will change all this. There is no escape from enculturation short of death. And even then, how death Is defined, what is done with the body, what ceremonies are followed, and how the surviving family responds will be dictated by cultural precedent.