Chapter 1 Nature and Scope of Logic PDF

# Chapter 13: Definition and Uses of Logic ## 1. Introduction Logic is one of the most important branches of philosophy. It shall be worth while to study its definition and uses in this chapter. First of all, it is necessary to take up the word “Logic” and explanations of its meaning. This word is...

# Chapter 13: Definition and Uses of Logic ## 1. Introduction Logic is one of the most important branches of philosophy. It shall be worth while to study its definition and uses in this chapter. First of all, it is necessary to take up the word “Logic” and explanations of its meaning. This word is derived from a Greek word "Logike" which is further connected with "Logos". It is used in two senses—(1) Thought and (2) Word. Therefore, Logic may be related to both thought and word. The fields of thought and word are different, and we will have to decide whether Logic is concerned with one field or the other. But one thing is clear that thought and word have a deep relation amongst themselves because thoughts are always expressed in words. Therefore, it is possible that Logic may be interested in such thoughts as are expressed in words. The subject-matter of Logic is also included. It is possible to think without language, and therefore, expression of thought in words should be treated as an inseparable part of thought. Some modern Logicians see a deep relationship, and therefore, they are preparing a system of symbols for thoughts which is known as Symbolic Logic. Since the literal meaning of Logic leads us to this conclusion that Logic is concerned with thoughts and their expression in words. ## 2. Definition of Logic Various writers have defined Logic differently. Here are some of the noteworthy definitions from these writers - - According to Thomson, "Logic is the science of the laws of thought". - Aldrich says, "Logic is the art of reasoning". - Whately defines, "Logic as the science and art of reasoning". - According to Hamilton, "Logic is the science of the formal laws of thought". - J.S. Mill writes, "Logic is the science of understanding and intellectual operations of advancing from known truths to unknown". From a study of these definitions it becomes clear that some writers prove Logic to be a science while another, an art; some describes it as a formal science, where another, a material science. As a result of these divergent attitudes of Logicians, we find a number of controversies about the real nature of Logic. Against the background of these traditional definitions, there are a few important definitions formulated by the modern writers. For example, Wolf writes, "Logic is the study of the general conditions of valid inference or proof”. Cohen and Nagel confirm this definition when they write, "Logic is the science of weight of evidence". Similarly, Kreyche says that Logic is the science of truth of thought and principles of truth. Some of these definitions appear to be incomplete, and we can arrive at a complete definition of Logic by combining bits from them in the following manner - Logic is a normative science of the laws of valid thought. This definition cannot be easily understood unless we are able to explain the meanings of the various words used therein; these words are - 1. Science 2. Normative Science 3. Laws 4. Validity 5. Thought **1. Science.** Logic is a science, but we must know the exact meaning of this word "science" in the first instance, and secondly, it must also be clear as to why logic is called a science. **a) Science is a kind of knowledge.** Science is derived from the word "scientia", which also means knowledge. Therefore, science means knowledge. But every type of knowledge cannot be called to be a science. Knowledge must have certain characteristics in order to be a science. Some of these characteristics are as follows - - Science is a systematic knowledge about a special subject-matter. In order to study the various things in this world, we divide them into different fields. Specialised knowledge about a department of nature is called a science. On the other hand, knowledge about all the things, is not a science but philosophy. For example, special knowledge of plants is called the science of Botany, and systematic knowledge about the working of mind is Psychology, which is again a science. Every science is based on certain definitions, ideas, and laws, which form a system of knowledge, when they are organised, Such a systematic knowledge is called a science. - Science is methodical and classified knowledge. The common sense knowledge of an ordinary man is not organised because it is not based on a method, nor is it classified. But scientific knowledge is based on the application of a definite method. This method is known as the scientific method. Every science seeks to explain facts. These facts are obtained through observation. A science discovers laws to explain these facts. To discover a law and to prove it is a long process, which is exactly that which scientific method does. This method is also based on classification of things so that knowledge about them gets organised, making the task of discovering their laws easier. Such a methodical and classified knowledge is called a science. - Science is proved knowledge. Common sense is raw knowledge, which stands in need of proof, on verification, it can turn out to be false. But on the other hand, science is that knowledge which has been established to be true. That is why scientific knowledge is certain. Any doubt about its truth can be removed by verification of it. Such a well-established knowledge is approved by authorities in the relevant field. Hence, only well-established and proved knowledge is called a science. By combining the above three characteristics of science, we can arrive at a definition of science - “*Science is a body of specialised, methodical and established knowledge about a subject-matter*". There are many sciences. They can be told apart on the basis of their separate fields with which they deal. All sciences can be further divided into three categories - - **Physical Sciences** which deal with physical matter and are exact such as Physics and Chemistry. - **Biological Sciences** which study life in plants and animals. Botany and Zoology come under this head. - **Human Sciences** which deal with human beings. Psychology and Social Sciences can be called human sciences. Physical sciences alone can yield exact and quantitative knowledge of things. That is why some writers reserve the use of this word "science" for only physical sciences. But other non-physical sciences are called sciences by virtue of the fact that they give us classified and methodical knowledge. So, any systematic knowledge has the right to be called science. **3. Laws.** Logic is a science, but we must know the exact meaning of this word "science" in first instance, and secondly, it must also be clear as to why logic is called a science. **a) Science is a kind of knowledge.** Science is derived from the word "scientia", which also means knowledge. Therefore, science means knowledge. But every type of knowledge cannot be called to be a science. Knowledge must have certain characteristics in order to be a science. - **Natural Laws.** A Natural law is the statement of the uniformity of natural events. In a particular field, events happen uniformly so that they can be described by a single statement; this statement of the uniformity of events, becomes a natural law. For example, the law of Gravitation of Newton is a natural law because describes the fact that things fall to the earth due to its attraction. Since natural laws describe a fact as it is, therefore their nature can be shown by "is". The natural laws are universal and are applicable on all the things of their respective field. For example, the law of Gravitation is applicable on all things in the universe, on the Earth, on the Moon, etc. It is not possible to violate natural laws. Any attempt to violate the law of Gravitation will itself be a case of this law. - **Political Laws.** A political law is an order from a parliament, king, or a dictator to regulate the affairs of society for its welfare. This law is of the nature of an order or a command. It is applied on the life of the public, and the aim is their welfare. This order is passed by a Govt. or a king. For example, the Indian Constitution is such a system of political laws under, which the Govt. in India works. The Indian Penal Code is another example of laws under which punishment is given to the guilty, according to the crime committed. Since political laws are of the nature of an order, therefore their nature can be expressed as "Must" - a particular action must be done. "Must" conveys the sense of a power behind the law which compels a person to do an action. Political laws like natural laws are not universal, because they may be different in different countries of societies. The political laws in the USA are different from those in India. Political laws can be violated, and there is a provision to punish all those who break them. - **Normative Laws.** The laws which are imposed for the realisation of some ideal, are known as normative laws. The law of nature are of Aesthetic which are acceptable on logical because violation of these laws follow, then laws of Norm which we accept for ourselves. For example, the absence of laws can be expressed by “should.” For they hold good in all conditions, places, aesthetics laws cannot lead to beauty. If our aim is to realize truth, then laws of logic are applicable. For example, the conditions, places, and organs. For example, truth cannot be achieved by violating the logical laws. It is clear from this account that logical laws are followed for the realization of the ideal of truth, therefore, the laws of Logic are normative laws. **4. Validity.** The meaning of "valid" is true or correct. Some writers like Wolf make a distinction between valid and true; valid means that which is logically consistent and true means that which is both logically consistent as well as consistent with facts. Here true means completely true. Logic aims at truth. It seeks to judge thoughts, whether they are true or false. But the question is what truth is. How can we judge what is valid or what is invalid? We need some principles for determining truth. There are two such principles at the root of the entire logical process of arriving at truth - **i) Absence of self-contradiction.** According to this law, if any statement contradicts itself or opposes itself, it cannot be true. In other words, if there is self-contradiction in a statement, it is false, and in order to be true, it must be free from self-contradiction. For example, a witness of theft says that at the time of theft, it was pitch dark and nothing could be visible, and he further says that he saw the thief at a distance and could recognize him also. The lawyer will at once point out to the self-contradiction in the statement of the witness and shall prove the witness to be false. Hence according to this principle of truth, whatever contradicts itself cannot be true, and in order to be true, it must be free from self-contradiction. Some idealistic writers like Hegal consider the law of self-contradiction to be the sole criterion of truth, they further maintain that logic does not need the second principle of consistency with facts for determining truth, but their view is one-sided and is therefore, not acceptable, because it is based on a metaphysical consideration. **ii) Principle of consistency with facts.** According to this rule, a statement must be consistent with facts in order to be true. If it is not according to the facts obtainable in the Nature, it is false. For example, a person while sitting in his own room, says that it is raining outside, his statement is true only if we go out and find that it is raining there. If it is not raining, then his statement is false. Therefore, there is the law of truth that in order to be true, a statement must be consistent with facts. The realistic writers as opposed to idealists, regard this principle as the basis and sole principle of truth. This again is a sectional view and therefore not acceptable. On the basis of these two principles of truth, Logic is divided into two parts, (a) Deductive Logic and (b) Inductive Logic. The principle of self-contradiction is the basis of Deductive Logic, it applies this rule on thoughts and statements and sees to it that there is no self-contradiction in them. The application of this principle yields formal truth, and Deductive Logic is also known as Formal Logic. Inductive Logic on the other hand is based on the second principle of consistency with facts and examines that a thought or statement corresponds with facts or not. By doing so, we achieve material truth, and Inductive Logic is also known as Material Logic. But here we must bear in mind that in order to be fully true, a statement must be true according to both the principles, i.e. it will have to be free from self-contradiction, as well as consistent with facts. Both deduction and induction together make Logic. It is divided into two parts, only for the sake of division of labour, otherwise both parts aim at the same truth. The two parts, are two different methods of arriving at truth; they have different laws as their basis. But on the other hand, whole truth can be achieved by the application of both the methods. Formal and Material Validity. The two parts of Logic are Deduction and Induction. But Deduction is known as formal Logic, and Induction is known as material Logic, and their aim is to achieve formal and material validity respectively. But what are formal and material validities? In order to explain this, we will have to make a distinction between form and matter. Everything has its form and matter. Form is its shape, and matter is the stuff, from which it is made. For example, the shape of a table is its form, and the material of which it is made, is its matter. It is possible that two things, may have the same form, but different matter, for example two tables are round, but one is made of wood. In the similar manner, things have the same matter, but different forms, for example, two tables are similarly form and matter of thoughts, statements. They are two aspects of a thing and as such they are always present in it, at the same time. Form and matter can only be distinguished in our thought. For example, the following two statements are similar in form, but differ in matter - - All men are rational. - All planets are moving heavenly bodies. Both have the same form, which is of the nature of "All something are something", i.e. "All X are Y", but matter is different, i.e. in one we talk of men and in another we talk of planets. In the same way, the two statements may have the same matter, but may differ in their form. For example - - All friends are selfish. - Some friends are selfish. It, therefore, it is clear that one argument may be true in form, but false in matter, for example - - All flowers are beautiful. - All men are flowers. Therefore, all men are beautiful. This argument is true in form but false in matter because the statement "All men are flowers" does not correspond with facts. Similarly, an argument may be materially ture but formally wrong, for example - - All Punjabis are Indians. - All Bengalis are Indians. Therefore, all Bengalis are Punjabis. So, far the matter of this argument is concerned, there is no mistake, but its falsehood arises out of its faulty form. It is, therefore, necessary that we may examine the formal and material validity of arguments separately. This task is undertaken by the two parts of Logic. Deductive Logic aims at formal validity of thoughts. Complete truth consists of both formal as well as material truth. In other words, an argument will have to be both formally as well as materially valid in order to be completely valid. **5. Thought.** Logic is mainly concerned with thoughts. It is not concerned with the mental process of thinking which goes on in the mind, because nobody can examine its truth or falsehood, unless it is expressed in language. It is only with the expressed thoughts with which Logic deals. But even then, we will have to learn about the structure of thought. There are three levels in the composition of thought, and at each level, different constituent comes to light. These three components of the composition of thought - **i) Concept** A general idea of things is called concept. When we use a word, some idea is present in the mind as its meaning; that idea is the concept. For example, "Chair" indicates all objects called chairs. Hence "Chair" expresses the class of chairs. And in the meaning of this word, all the qualities possessed by them. In the same way, table, books, man, country, etc. are concepts. When a concept is expressed in words, it is known as term. **ii) Judgement** The process of relating two concepts is called Judgement. Often we compare two concepts to see whether a relation between them exists or not. Thus, this relation, may be positive or negative. For example, when we say that students are intelligent, there is a positive relation between students and intelligence, but when we say that students are not intelligent, there is a negative relation between them. The process of judging also, goes on in the mind, but when judgement is formed and is expressed in a sentence, it is called a proposition. The process of passing from one or two judgements to a new judgement is known as reasoning or inference., For example, from the judgemenst "All men are mortal" we pass on to another judgement "Socrates is mortal". In this reasoning, the first judgement is the basis, and it is on to another argument. In fact, Logic is to deal with these inferences or arguments which are results of our reasoning. But in order to examine the validity inferences, we will have to analyse them into concepts, and judgement for study. **iii) Reasoning** Some writers regard Logic as the science of proof or evidence as we have seen it in the definition of Logic by Cohen and Nagel. A distinction between inference and proof will have to be made. Inference is a process of arriving at a conclusion, from given data, but proof means, the process of providing evidence for a statement; the two processes are different, because proof is used for valid inference, or complete evidence always, but inference, on the other hand, can be either valid, or invalid. From the explanation of the meanings of all the terms, used in the definition of Logic, it is clear that the aim of Logic is truth, or validity. For this it frames some laws and rules. The study, of such laws of validity is Logic. ## 3. Scope of Logic Logic is a science and every science has its own field or province of things with which it deals. All things for this purpose, can be divided into many fields, and in order to acquire knowledge about each field, we have a separate science. For example, Botany studies plants, Zoology studies, all animals. Anthropology studies Human Beings. Hence, every science has its own department of facts— this province which demarcates the boundaries of a science, is its scope. All the things or facts, which fall with in the boundaries, constitute its subject-matter. Thus, scope and subject-matter of a science, are not different; only scope expresses its boundaries, and subject-matter, expresses, its class of things with which it deals. Now the question arises as to what is the scope or subject-matter of Logic? This is clear, from the literal meaning of the word "Logike", which carries two senses, in Greek language - thought and word Hence both thoughts and words must fall within the scope of Logic, but words are a part of Language, and as such they fall within the scope of Grammar. If words and language is not separated from thought, a confusion is bound to arise. There is another point, to be seen here. Every thought of word, indicate things or objects, which are present in the physical words. So, there are three things before us - (i) thought, (ii) word, (iii) thing. We will have to decide, between them as to which is the true scope of Logic. On this there is a regular controversy between Logicians, and the following views have emerged - **(i) Conceptualism** Conceptualism maintains that concepts or thoughts is the only subject-matter of Logic. Hammilton confirms this view and observes that Logic is the science of the formal laws of thought. Nominalism on the other hand states that it is with words, that Logic deals - Whately supports this view. He says that Logic is the science of Linguistic consistency. According to Realism, the things of facts constitute the true subject-matter of Logic. For example, J.S. Mill who is the great supporter of realistic school, writes that Logic is the investigation of material truth. These writers put forward arguments to prove their own view. In fact this controversy as to whether Logic is concerned with thoughts or words of things, is meaningless, because, Logic is primarily concerned with thought, reasoning, or inference, and since thought is expressed in words and about things, or facts, therefore, Logic has a secondary concern with words, and things. So, we come to this conclusion that thought is the subject-matter, or scope of Logic - the thought which is expressed in words and about things always. The thought is sometimes. taken to mean the mental process of thinking. Logic has got nothing to do with this mental process, because Logic is concerned with validity of thought, and validity of a thought cannot be judged, unless it is expressed in language. Hence, it is with the product of thinking, and not with the process of thought, that Logic deals. The process of thought, comes within the scope of Psychology. Logic is not interested to study, the conditions under which thinking takes place, but it examines its validity. It shall go into all those procedures and methods by which validity, of reasoning can be established. For this purpose, Logic makes use of two methods- Induction and Deduction. Induction goes from the particular facts, to general conclusions. Whereas Deduction goes from the general statements to particular conclusions. They work on different principles. Induction examines the validity on the basis of material evidence and aims at material truth. Deduction deals with the form of inference, and examines its formal validity. Its aim is to arrive at formal truth. It is, therefore, clear that truth or validity of inference is the true scope of Logic - a validity established by the two logical methods of Deduction and Induction. ## 4. Is Logic a Science or an Art? Sometimes, a question, is asked about Logic as to whether Logic is a science, or an Art, and the answer to it is not equally clear. The answer to this question, depends on what exactly, we understand by science, and art. We know that science means knowledge. This knowledge, must be systematic, and about a definite subject-matter. Therefore, science gives us knowledge. It is concerned with knowing. On the other hand, Art means skill to deal with a definite material. Through Art, we learn to physically deal with things; we manipulate them, change them, or construct them. So Art is concerned with doing. It is practical. Whatever relation of contrast exists between knowledge and action, the same holds true of science and Art; if science is knowledge, Art is skill, if science is theoretical, Art is practical. We should not lose sight of one point that knowledge and action are themselves related deeply, because they affect each other. Knowledge holds out light for action, and as such science guides activities of Art. Knowledge must precede actions. Without knowledge, Art can go astray without achieving the desired results. Art, on the other hand, is useful for science, because the ultimate goal of knowledge is some achievement, in practical life. The knowledge, which does not lead to Art, is hollow, and useless. There is no wrong in saying that Art is the fruit of science. If Art, without science, is rootless, science without Art is fruitless. In the light of this discussion about the exact nature of science and Art, we can now decide about the nature of Logic. We know, that Logic gives us knowledge about the laws of validity of reasoning, and as such Logic is a science. Thomson firmly says that Logic is a science. But on the other hand, reasoning is itself an art, which is learnt by practice. Therefore Logic is the Art of reasoning. Aldrich confirms this definition of Logic. But from the study of Logic only knowledge about the rules of validity is attained, and some people fail to make use of this knowledge in acquiring an art of reasoning. Hence, Logic can become an art, but it is not an art, as such. Therefore, primarily, Logic is a science, only secondarily, it is an Art. Whately regards Logic as both science as well as an art, which view, is not absolutely correct. ## 5. Logic is the Science of Sciences and Art or Arts Duns Scotus, said, "Logic is the science of sciences, and Art of Arts". But, we have to show, how this statement is true. We can do so in two parts. **(a) Logic is the science of sciences and** **(b) Logic is Art of Arts** **(a) In order to show that Logic is the science of sciences, the following evidence can be given.** - If we examine the names of most of sciences, we find that the word "Logy" is used therein. For example, Zoology, Biology, Sociology, Psychology, etc. Logy is the same as Logic. Logic means truth, reasoning, or true knowledge. Now, let see the word "Zoology", which is made of "Zoo" and "Logy". Logy means knowledge (truth) and "Zoo" means animals. This shows that logic knowledge of animals. In the same way, Sociology means knowledge of society. This shows that logic is implied in every science. This is not a proof, but this is definitely an additional evidence in favour of our contention. Every science investigates knowledge of those things, which fall in its, own field. Also wants to establish this knowledge, as true. In other words, every science seeks truth in its own field. But truth can be attained only by the methods of Logic. They are Deductives, and Inductive methods. Every science will have to use logical methods, in their respective fields, and achieve truth. In this regard, every science is based on Logic, and Logic is fundamental to all of them. That is why Logic is called the science of sciences. - Russell, and Whitened, the two great philosophers have written, a book called "Principia Mathematica", in which, they have tried to prove that the laws of Mathematics, are based on Logic. All physical sciences, are further based on Mathematics. These all sciences, should be based on Logic. Dr. Ray has done a research work, on the problem as to which of the sciences, are more fundamental. He found that every science is based on, one science or the other depending, on their fundamentality. Thus, he arranged all science in a descending order, of their fundamentality, and shown the result in the table - ``` Logic / Mathematics / Chemistry / Physics / Biology / Psychology / Sociology ``` From this table, it is proved that Logic is the most fundamental, of sciences which are based on its laws. Therefore, Logic is the science of sciences. - The laws of Logic are, regulative and they are to be followed, in all branches of knowledge. It may be true that every science, have its, own special subject-matter, of field and used its own method for research, but it has to ultimately depend, on the fundamental laws of Logic. The most basic, laws of every science further lead to Logical laws. It is because of the universality of its laws - that Logic is called the science of sciences. Welton, a great writer has put forward, this evidence in his book – “*A Manual of Logic*” to prove that Logic is the science of Sciences. **(b) Logic is also the Art of Arts.** We know the truth already, that Logic is an Art, also. It is an Art of correct thinking or valid reasoning. But correct thinking is fundamental to every activity of Art. We will have to manage the material, to the field of an Art, and this is possible only on the basis of correct thinking about it. Without right thinking, we cannot deal with it. If our thinking about the materials of Art, or its method or technique is wrong, the entire art goes wrong. For example, a carpenter makes a table, the measurement of its part, and their shape must be according to the whole of the table. If there is a mistake in the calculations anywhere, the table cannot be made. Or will be made wrong. It is therefore clear, that correct thinking is an art, and this art is basic to all arts. Hence it is proved that Logic is the Art or Arts. ## 6. Logic and Psychology Logic is dealt with thought and seeks to investigate its truth. In fact, Logic aims at truth. In order to attain truth, Logic frames a number of Laws and rules. A systematic study of the laws of truth is called logic. It is rather hand to be a normative science since its study of thought is guided by the standard of truth. On the other hand, psychology is a science of Mind. Psychology is made of two words “Psyche” and "logy.” Psyche means mind, and "logy", means science, so Psychology is the science of Mind. What is mind? Mind is nothing but that which observes, thinks, feels, hopes or wishes, and makes decisions. Willing (conative). For example, a person sees a flower, feels happy and likes to pluck it. Here seeing the flower is knowing, feeling happy is a feeling, and liking to pluck the flower is willing. Besides the mental processes, the external behaviour of the organism also comes under the scope of Psychology. Mind is always expressed, in behaviour. We can define Psychology as a science of mind, and bechology and animals. **Relationship.** There is a bound to be a deep relationship between Logic and Psychology because logic is concerned with thought and thought is a mental process, thus both the science, meet on the process of thought. Although the aims of these sciences are different, but Logic has to depend upon Psychology to explain the nature and composition of thought. Logic may be interested in truth of thought, but truth cannot be tested unless the structure of thought is examined. In this regard, Logic takes the help of Psychology. It is only through the analysis of Psychology that, we come to know the basic constituents of thought which are concepts, judgement and reasoning. In this way, Logic proceeds, on the basis of Psychological knowledge about the process and composition of thought. **The differences.** There are important difference in the scope, nature and approaches of Logic and Psychology. The following points in this regard may be noted - **1. Logic is a normative science while Psychology is a natural science.** Both of them are concerned with thought, but the aims of their study of thought are different. Logic examines the validity of thought, and tries and establish truth. Since it is guided by the standard of truth, therefore, it is a normative science. But on the contrary, Psychology aims at understanding the process of thought as it takes place. It does not judge whether it is true or false. Since Psychology is interested in the facts, about mind, as those facts are, it is a natural science. Hence Logic studies thought, as it should be, in order to be true, while Psychology studies thought as it is. Logic is a normative science where Psychology, is a natural science. **2. The scope of Logic is narrower than that of Psychology.** All the mental processes fall within the scope of Psychology. Behaviour, and all cognitive, affective, and conative process, are included in them. Psychology deals, with both men as well as animals, since both, have mind. Therefore the scope of Psychology is very vast. But the scope of Logic is confined, to thought only and is further limited to its truth, and it does not concern itself with thought as it is, therefore, the scope of Logic, as compared to that of Psychology is much narrow. **3. Logic is interested in the product of thought while Psychology is interested in the process of thinking.** Although both sciences deal with thought, but they, deal with two different aspects of thought. So long the thought goes on in the mind, in the form of a mental process, it remains the concern of Psychology. In this form, thinking is not the subject-matter of Logic, because we cannot examine its validity unless it is expressed in language. Logic is concerned with expressed thoughts which can be judged as true or false. Expressed thought is a product of thinking, which is a process in the mind. Hence logic, is concerned with the product of thought and not with the process of thought, whereas Psychology is concerned with the process of thought and not with its product. **4. Logic is interested only in general, abstract and intellectual knowledge while Psychology aims at all sorts of knowledge.** Psychology is sometime interested to show about the mental of one individual and this way is knowledge is not general, Its knowledge is about the concrete object, and is based on observable facts. On the other hand, the knowledge of Logic is universal and abstract. **7. Logic and Grammar** Thought and Language, are very much related, therefore, Logic and Grammar, must be related, because Logic is a normative science, of the law of validity of thought. If we use the word language, instead of thought in this definition, the same can very well serve as the definition of Grammar. Grammar is concerned with language. It seeks to examine its correctness. For, this purpose, Grammar frames many rules. A systematic study of such rules of the correctness of language is called Grammar. We can define Grammar as a normative science of the laws of correct language. **Relationship.** Logic and Grammar have the following points of relationship - 1. There is no doubt that the subject-matter of Logic is thought, and that of Grammar is language, but, since thought and language are deeply related with each other, it, therefore, Logic and Grammar must also be related. Thoughts are always expressed in words, and language is always expressed of thought. There cannot be thoughts without words and there cannot be language without thoughts to be expressed. Therefore, the science of thought, and science of language are bound to be related, in other words, there is a deep relationship between Logic and Grammar. Whatever relation exists between thought and language, the same relation must exist, between Logic and Grammar. 2. Logic is interested, in the validity and truth of thought. If a thought is correct in itself, but it is expressed in incorrect language, the same thought becomes incorrect. It is, therefore, necessary that for the expression of a correct thought, we need to express it in correct language. Therefore, it is essential that Logic should take into account, the basic rules of Grammar, in order to preserve the correctness, of thoughts. That is why Whately observes that for Logic, verbal consistency is necessary, for without it, thought is bound to be invalid. 3. Both Logic and Grammar are normative disciplines. Both of them provide systemic procedures to achieve definite standards. Logic aims at the realisation of the standard of truth, in thinking, and Grammar aims at the attainment of the standard of correct language. Therefore, the nature of both the studies is normative. **Differences.** It is true that Logic and Grammar, are very much related to one and other, but that does not mean, that they are, one, and there are no differences between the two. The following points of their difference must be borne in mind - 1. The subject-matter of Logic and Grammar, are different. Thought is the subject-matter of Logic, while language is the subject-matter of Grammar. It is true that though is always expressed in language, and truth appears before us in the same form, but the two aspects of one statement must be distinguished, one is its thought-content, and the other is its expression in words. The main concern of Logic is thought, and not language though which it is expressed. On the contrary, the main concern of Grammar is language, and not thought, which is communicated through it. Therefore, the subject-matters of both these studies are different. Logic is primarily concerned with thought, and secondarily concerned with language, but Grammar, is primarily concerned with language and secondarily, concerned with thought. 2. Grammar divides a sentences into many parts of speech for its study such as noun, pronoun, verb, adverb, adjective, conjunction etc, but in the field of Logic, on the other hand, a proposition, is divided only into three parts--(i) subject (ii) predicate and (iii) copula. For example, let, us analyse the statement logically-"All men are rational". In this, "men" is the subject, "rational" is the predicate, and "one" is the copula. Hence, both Logic and Grammar, differ in their analysis of sentences. 3. In Grammar, three tense, Past, Present and Future are used, but in Logic, only one tense is used that, is eternal, and must be expressed in the present tense. If one thing was true yesterday, it is true today. Logic, one tense is used in the present tense. This is the reason that Logic, is the past or it shall happen in the future, truth. For example, the disentient tense. This is the reason that Logic, is the past or it shall happen in the future, truth. For example, the disentient tense. This is the reason that Logic, is the past or it shall happen in the future, truth. For example, the disentient tense. This is the reason that Logic, is the past or it shall happen in the future, truth. For example, the disentient tense. This is the reason that Logic, is the past or it shall happen in the future, truth. , it is true today, and it shall be true tomorrow, it is true today. If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense. If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true today. Logic changes the statements, into the present tense, If one thing was true yesterday, it is true