Logic and Philosophy PDF

Okay, here is the conversion of the document and images into a markdown format. ### Different departments for its study A science confines its investigation to a particular department. Scientific knowledge is a general knowledge of the facts belonging to that department. Such knowledge must be cons...

Okay, here is the conversion of the document and images into a markdown format. ### Different departments for its study A science confines its investigation to a particular department. Scientific knowledge is a general knowledge of the facts belonging to that department. Such knowledge must be consistent, methodical and systematic. It is based on reason. It must be verifiable in nature. If and when verified it is regarded as exact and accurate and thus it is certain. ### Reasoning Reasoning is a mental process of passing from something known to something unknown. Reasoning when expressed in language is called an argument. In reasoning, 'the something known' constitutes the data or materials of reasoning. In an argument the data are known as the premises, and the new knowledge is known as the conclusion. Thus, in an argument we proceed from the premise or premises which are given, to the conclusion at which we arrive on the basis of the premise or premises. Reasoning or inference may be divided into Deductive and Inductive. In a deductive inference, the conclusion is drawn from one or more given premises. The conclusion cannot be more general than the premises in a deductive inference which is mainly an inference "from general to particular. For example: All men are mortal All politicians are men All politicians are mortal. In an inductive inference, a general conclusion on the basis of some observed facts. The conclusion is more general than the premises in an Inductive inference which is mainly an inference from 'particular to general For example: * Ram is mortal * Hari is mortal * Jadu is mortal * Madhu is mortal * All men are mortal. Reasoning is the main subject-matter of Logic. Logic gives us a systematic knowledge of certain principles which regulate our reasoning for the realization of truth and avoidance of error. As logic is a scientific discussion of reasoning, so logic is called the science of reasoning. ### 1.3 Nature of Logic: In order to determine the real nature of logic, the following points are to be considered. 1. Logic is concerned with Mediate knowledge, not with Immediate Knowledge: Knowledge is a system of ideas corresponding to a system of things accompanied by a belief in such correspondence. If we analyse knowledge, we find that knowledge involves three factors: * (1) A system of ideas in the mind. * (2) Correspondence of these ideas with a system of actually existing things. * (3) A belief in such correspondence. For example: We say, 'We know the Sun'. It means that- we have, in our mind the idea of a heavenly body of enormous size, with dazzling brilliance around which the planets revolve; corresponding to this idea in the mind, there is the Sun that actually exists; and there is also the belief that the Sun exists. Forms of knowledge: Knowledge may be of two kinds- 1. Immediate knowledge. 2. Mediate knowledge. Immediate knowledge is that knowledge which is derived from perception- external and internal. We directly come to know the objects of the external world by means of external perception. For example: the Sun, the Moon etc. Again, we directly know our own mental states by means of internal perception. For example, our joys and sorrows. Mediate knowledge is that which is obtained through the medium of some other knowledge. The source of mediate knowledge is inference, testimony and authority. Mediate knowledge is also called indirect knowledge. Now, the question is- With which of these two forms of knowledge is Logic concerned? Majority of logicians maintain the view that Logic is concerned only with mediate knowledge. According to these logicians, Logic is primarily concerned with the problem of proof. We want to prove the truth of something in Logic. Immediate knowledge does not require any proof. What is directly known by perception is certain by itself and is true in normal circumstances. The question of proof does not arise in such cases. But, mediate knowledge requires proof for establishing its validity. There is the possibility of error in case of the knowledge derived from inference, testimony and authority. Such knowledge requires proof. Thus, the view that Logic is concerned with mediate knowledge only appears to be ## Correct one. According to Indian Logic, Logic is concerned with all forms of knowledge #### 2. Logic is concerned with both Formal Truth and Material Truth. ##### Form and Matter of Thought: Every material object has two aspects-form and matter. For example, a coin is round in shape and is made of gold. A table is rectangular in form and is made of wood. There is a close relation between form and matter. There cannot be matter without any form or form without any material. Various things made of the same material may have different forms; again, various things of different materials. Thought has also these two aspects- form and matter. By 'the matter of thought' is meant the things thought about. And by 'the form of thought' is meant the way in which the mind thinks about them. In case of thought also, the form may change while the matter remains the same. Again, the matter may change while the form remains the same. In one sense, truth means consistency among ideas or thoughts themselves. In another sense, truth means correspondence of thoughts or ideas with facts or things of the world. From these two senses of truth, a distinction is drawn between formal truth and material truth. Thus, there are two aspects of truth: Formal Truth and Material Truth. Formal Truth means self consistency or freedom from self- contradiction amongst thoughts themselves. The expression 'circular rectangle', for example,this self contradictory. It is unthinkable, inconceivable in itself. So, this is not formally true. But, the expression 'a round circle', for example, is formally true. Material Truth means correspondence of thoughts with things of the actual world. It consists in the correspondence of our ideas or thoughts with actually existing facts. For example, the expression 'green leaves of a tree' is materially true as the idea corresponds with a fact. But, the expression 'golden mountain' is not materially true as the idea does not correspond to anything actually existing in the world. It should, however, be noted that formal truth and material truth do not always go together. Whatever is materially true, is also formally true; but whatever is formally true, may not be materially true. In Western Logic, two broad divisions of Logic-Formal and Material have been recognized on the basis of this distinction between formal truth and material truth. Formal Logic aims at the attainment of formal truth. It is concerned merely with the forms of thought. It deals with thoughts which are consistent among themselves. In formal logic, we do not question about the truth of the premises of an argument. The premises are assumed to be true. We only examine whether the rules of the argument have been observed properly and whether the conclusion necessarily follows from the premises. Formal Logic is also known as Pure Logic or Logic of Consistency. Material Logic aims at the attainment of material truth. It deals with thoughts which must agree with the actual facts of the world. In material logic, we are concerned with the question whether the premises are true as a matter of fact and also whether the conclusion corresponds to the actual fact of the world. Material Logic is also known as Applied Logic or Logic of Truth. Generally, deductive logic is called formal logic as it aims at formal truth. Inductive logic is called material logic as it aims at material truth. Logic is concerned both with formal and material truth. Therefore, Logic is both Formal and Material. Logic determines the regulative principles of correct thinking and prescribes those principles to be observed in order that thinking may be correct and errors may be avoided. In case of an argument, if in drawing the conclusion from the premise or premises the rules of the particular form of the argument have been properly observed, then that argument is formally true. Again, an argument is materially true if the propositions constituting it agree with actual facts of the world. In fact, formal truth and material truth are complementary to each other. Truth is essentially one and indivisible. In its fullest sense, truth implies both formal truth and material truth. Taken separately, they are two aspects of truth. The distinction between formal truth and material truth is made only for convenience of treatment. In Indian logic, there is no such distinction between formal and material truth. Logic is concerned not merely with formal truth, but also with material truth. ## UNIT 1: LOGIC ### Definition, Nature, Scope and Utility, Traditional and Modern logic #### 1.1 Introduction: Man is a rational animal. Man is a kind of animal like all other animals. But rationality' distinguishes man from other kinds of animals. Man's power of thinking emerges from rationality. Human thinking may not be always correct. To arrive at valid knowledge, thinking must be correct. Truth can be realized by means of valid knowledge only. Realisation of Truth is the ultimate end of all human pursuit after knowledge. Human thinking must proceed in and through some correct and systematic ways for the attainment of truth. Logic formulates certain principles of correct thinking. Thinking must observe these principles so that it may be correct. It is possible to arrive at valid knowledge by means of correct thinking only. The ideal of truth can be attained by such valid knowledge. #### 1.2 What is Logic: The word 'Logic' is derived from the Greek word 'Logike'. 'Logike' is the adjective of the noun 'Logos'. The Greek word- 'Logos' means thought' or word' as the expression of thought. Hence, etymologically the definition of Logic is- Logic is the science of thought as expressed in language. However, the word 'Thought' is highly ambiguous. It may mean perception, memory, imagination, general idea or concept, reasoning etc. The word 'reasoning' may be substituted for 'thought' in logic for clarity. Logic is generally defined as a science of reasoning: This provisional definition can be discussed briefly at present to have a general idea of the nature of logic. Science: A science is a systematic body of knowledge relating to a particular department of nature. For example- Physics, Botany, Psychology etc. are sciences. ##### Logic refers to thinking ### Logic is concerned with Mediate knowledge #### 1. Logic is concerned with both formal truth and material truth ### Logie is both a Science and the Art ##### Logie is a normative Science ### Various Definitions of Logic: ### Logic is the Art of reasoning" #### 2. Logic is the science of argumentation" ### Logic is the science as well as Art of The science of reasoning #### 4. Logic is the sciene of the operations of the understanding which are subservient to --- ### Generally, Logic is called a science of thought #### 2. Logic is primarily concerned with the problem of proof ##### The main subject-matter 3. ### Judgement 5. #### 6. ### Logic is concemed with valid 7 #### 8 ### #### 3 ### Logic Is both a Science and the Art ### Logic is the sciene of sciences and Art of arts ##### Logic As A Nomative Science ### Logic is imporant in daly life also ### Logic ###### Logie does teach us reason ### Logic utility has sometimes