S. B. STNHA, C. J. ( 1 ) THESE writ appeals involving common questions of law and facts were taken up for hearing together and are being disposed of by this common judgment. ( 2 ) THE respondent in both the writ petitions is the appellant. The writ petitioners-respondents filed the writ petitions praying issuance of writ of or order in the nature of mandamus directing the appellants to consider their cases for promotion to the posts of Post-Graduate teachers in English against the existing vacancies. The facts are taken from Writ petition No. 21559 of 1999. ( 3 ) THE writ petitioner was working as a Trained Graduate Teacher in A. P. Residential School for Girls at Medak, which was under the control of the appellant- society. She was trained in Bio-Sciences as Graduate Teacher in the year 1985, she had acquired the qualification in English in Post-Graduation and obtained Post- graduate Degree in English in the year 1995 in III Division and improved upon appearing in the examination again in the year 1996 wherein she got II Division. When a vacancy for Post-Graduate Teacher arose, she applied therefor but had not been considered. According to the writ petitioner/respondent as she has possessed P. G. Degree in English and also Degree in B. Ed. , with two years teaching experience, she fulfils the requisite qualification. ( 4 ) THE contention of the appellant, on the other hand, is that the writ petitioner does not fulfil the requisite qualification. The qualifications prescribed for promotion from the post of Trained Graduate Teacher to the post of Post-Graduate Teacher in terms of Rule 5 (a) of the Service (Recruitment) Rules, 1972 are as follows:" (A) I or II Class MA. /m. Sc. , Degree with not less than 50% of marks; (b) 1 or II Class B. Ed. , Degree; (c) Atleast two years teaching experience as TGT in a Residential School of the society". ( 5 ) THE said rule underwent amendment, which is to the following effect:" (A) For the Rule (a) the words "in the relevant subjects" shall be added. (b) For the Rule (b) the words "with relevant subject as one of the methods of teaching" shall be added". ( 6 ) INTERPRETATION of the aforementioned rules came up for consideration in U. Giridhar kishore v. APREI Society, Writ Petition no. (b) For the Rule (b) the words "with relevant subject as one of the methods of teaching" shall be added". ( 6 ) INTERPRETATION of the aforementioned rules came up for consideration in U. Giridhar kishore v. APREI Society, Writ Petition no. 20533 of 1995 and batch dated 24-10-1997, which was disposed of by a Division Bench consisting of P. Venkalarama Reddi, J, as his Lordship then was and A. S. Bhate, J. , their Lordships noticed:"in the case of some of the petitioners, for eg. , in WP. Nos 27117/95, 15056/96 and 21041/96 etc. , promotions were denied for the additional reason that in B. Ed. , they did not study the methods of teaching the relevant subject for which promotion is sought". ( 7 ) THE question, which arose for consideration in those writ petitions, was as to whether in the absence of any amendment in clause (c) of Rule 5 (a) of the Rules made by the appellant-society, the teaching experience as Trained Graduate Teacher in residential school of the society in the relevant subject was also necessary. Answer to the said question was rendered in negative on the premise that the words cannot be read into clause (c), which was interpreted all through since its inception and acted upon in a particular manner. ( 8 ) AS regards the writ petitions wherein petitioners did not fulfil the qualification contained in clause (b) of the aforementioned rules, the learned Judges held:"as far as WP Nos. 27117/95, 26295/96, 2917/95, 4199/96, 15056/96 and 21041/96 are concerned, they are liable to be dismissed straight-away inasmuch as according to the information furnished by both the Counsel for the petitioners, these petitioners do not satisfy the requirement of clauses (b) of the rule as they did not study the relevant subject as a method of teaching in the B. Ed. , course we do not find any infirmity in the rule laying down the condition of post- graduation and B. Ed. , degree in the relevant subject". ( 9 ) HOWEVER, the same Division Bench while disposing of another writ petition, being Writ Petition No. 18718 of 1995, on the same date, considered the case of s. Nagendramma and another wherein the writ petitioners fulfilled the qualification contained in clause (c) of Rule 5 (a) of the aforementioned Rules, but did not fulfil the criteria contained in clause (b) thereof. In that case, the writ petitioners had been teaching Chemistry and Physical Sciences for Intermediate Classes for two years and post-Graduate teacher posts fell vacant. Having regard to the peculiar fact situation obtaining therein the learned Judges observed:"however, it is brought to our notice that the first petitioner has been teaching Chemistry for Intermediate Classes since the last two years. Hence, in the light of this subsequent event, she has to be considered for promotion as PGT in Physical Science. Otherwise, as rightly pointed out by the learned Counsel for the petitioner, at no point of time, she can aspire to get promotion as she will be lacking one or the other criteria. The denial of promotion to her forever would be unjust and violative of Article 16 of the constitution". ( 10 ) THE learned single Judges by reason of the impugned judgments dated 27-4-2000 and 30-12-1999 allowed the Writ Petition nos. 20758 of 1999 and 21559 of 1999 respectively following the judgment in the aforementioned Writ Petition No. 18718 of 1995. ( 11 ) RULE 5 of the aforementioned rules provided for the method of recruitment. As noticed hereinbefore, essential qualifications for holding the posts of Post- graduate Teachers had been rendered therein. All the clauses contained therein signify essential qualifications. ( 12 ) AS noticed hereinbefore, the Bench while disposing of Writ Petition Nos. 20533 of 1995 and Batch held that those petitioners who did not satisfy the qualifications as specified in clause (b) were not entitled to be granted any relief and purported to have moulded the relief in Writ Petition No. 18718 of 1995. ( 13 ) HAVING considered the matter, we are of the opinion that whereas in Writ petition No. 20533 of 1995 and batch, the division Bench laid down the law, in writ Petition No. 18718 of 1995 reliefs were only moulded ex debito justitiae. ( 14 ) MR. C. V. Nagarjuna Reddy, learned counsel appearing on behalf of the writ petitioners/respondents, however, would submit that keeping in view the fact that in this case also the writ petitioners satisfy the criteria laid down in clauses (a) and (c) but do not fulfil the criteria as contained in clause (b) of the aforementioned rules, the decision of the Division Bench in s. Nagendramma (supra) should be followed. Mr. Mr. Reddy would urge that having regard to the fact situation obtaining herein, the rule should be read down as otherwise the writ petitioners may be deprived of their chances of promotion. We are afraid that such a contention cannot be accepted. It is now beyond any cavil of doubt that essential qualifications cannot be relaxed. Recourse to reading down of a provision can be had only with a view to save it from being struck down on account of its unconstitutionality. ( 15 ) IN Delhi Transport Corpn. v. DTC mazdoor Congress, AIR 1991 SC 101 , it has been held:"it is thus clear that the doctrine of reading down or of recasting the statute can be applied in limited situations, it is essentially used, firstly, for saving a statute from being struck down on account of its unconstitutionality. It is an extension of the principle that when two interpretations are possible one rendering it constitutional and the other making it unconstitutional the former should be preferred. The unconstitutionality, may spring from either the incompetence of the Legislature to enact the statute or from ils violation of any of the provisions of the Constitution. The second situation which summons its aid is where the provisions of the statute are vague and and ambiguous and it is possible to gather the intentions of the Legislature from the object of the statute, the context in which the provision occurs and the purpose for which it is made. However, when the provision is cast in a definite and unambiguous language and its intention is clear it is not permissible either to mend or bend it even if such recasting is in accord with good reason and conscience. In such circumstances, it is not possible for the court to remake the statute. Its only duty is to strike it down and leave it to the legislature if it so desires, to amend it. What is further, if the remaking of the statute by the Courts is to lead to its distortion that course is to be scrupulously avoided. One of the situations further where the doctrine can never be called into play is where the statute requires an extensive additions and deletions. Not only it is no part of the Court s duty to undertake such exercise, but it is beyond its jurisdiction to do so". One of the situations further where the doctrine can never be called into play is where the statute requires an extensive additions and deletions. Not only it is no part of the Court s duty to undertake such exercise, but it is beyond its jurisdiction to do so". ( 16 ) FURTHERMORE, in a case of this nature, such construction, which gives effect to the purpose and object of the Rules, must be taken recourse to. For the purpose of interpretation of a statute, one must take into consideration the law as it stood before amendment and the mischief sought to be remedied by reason of an amendment. If the submission of Mr. Reddy is accepted, the very purpose of amendment in Rule 5 (a) and (b) shall become otiose and absolutely redundant. Such interpretation in the aforementioned situation cannot be taken recourse to. ( 17 ) IN Anemia Kumar Bej v. State of west Bengal, 1999 (5) SLR 115 (Cal.), a division Bench of Calcutta High Court noticed: it is a well settled principles of law that despite absence of a rule, the Selection committee is entitled to short list the candidates. Rule 9 (c) (ii) of the Rules only gives a statutory recognition to the aforementioned service jurisprudence In a case of this nature, therefore, trie doctrine of purposive interpretation should be invoked, and in such a situation the word written test must be held to be incorporated within the word interview . The answer to the question posed in this appeal, thus in the opinion of this Court, should be rendered in affirmative as otherwise the word written examination would become totally otiose. Such a construction is permissible by taking recourse to the doctrine of strained construction, as has been elaborately dealt in by Francis Bennion in his Statutory -Interpretation , At Section 304, of the treatise purposive construction, has been described in the following manner :-"a purposive construction of an enactment is one which gives effect of the legislative purpose by- (a) following the literal meaning of the enactment where that meaning is in accordance with the legislative purpose (in this Code called a purposive-and- literal construction), or (b) applying a strained meaning where the literal meaning is not in accordance with the legislative purpose (in the Code called a purposive-and-strained construction ). " ( 18 ) IN DPP v. Schildkamp, (1971) ac 1, it was held that the rule that severance may be effected even where the blue pencil technique is impracticable. ( 19 ) IN Jones v. Wrotham Park Settled estates, (1980) AC 74, the law is stated in the following terms:-". . . I am not reluctant to adopt a purposive construction where to apply the literal meaning of the legislative language used would lead to results which would clearly defeat the purposes of the Act. But in doing so the task on which a Court of justice is engaged remains one of construction, even where this involves reading into the Act words which are not expressly included in it. Kammins Ballrooms Co Ltd v. Zenith investments (Torquay) Ltd. , (1971 AC 850) provides an instance of this; but in that case the three conditions that must be fulfilled in order to justify this course were satisfied. First, it was possible to determine from a consideration of the provisions of the Act read as a whole precisely what the mischief was that it was the purpose of the Act to remedy; secondly, it was apparent that the draftsman and Parliament had by inadvertence overlooked, and so omitted to deal with an eventuality that required to be dealt with if the purpose of the Act was to be achieved; and thirdly, it was possible to state with certainty what were the additional words that would have been inserted by the draftsman and approved by Parliament had their attention been drawn to the omission before the Bill passed into law. Unless this third condition is fulfilled any attempt by a court of justice to repair the omission in the act cannot be justified as an exercise of its jurisdiction to determine what is the meaning of a written law which Parliament has passed". ( 20 ) IN Principles of Statutory Interpretation of Justice G. P. Singh, 5th Edition, 1992, it is stated:-"the Supreme Court in Bangalore Water supply v A. Rajappa, ( AIR 1978 SC 548 ) approved the rule of construction stated by denning, L. J. while dealing with the definition of industry in the Industrial disputes Act, 1947. The definition is so general and ambiguous that BEG. The definition is so general and ambiguous that BEG. C. J. said that the situation called for "some judicial heroics to cope with the difficulties raised" k. Iyer, J. , who delivered the leading majority judgment in that case referred with approbation the passage extracted above from the judgement of Denning, L. J. , in Seaford court Estates Ltd. v. As her. But in the same continuation he also cited a passage from the speech of Lord Simonds in the case of magor and St. Mellons R. D. C. v. Newsport corporation, 1951 (2) All ER 839, as if it also found a part of the judgement of denning. , LJ. This passage reads: "the duty of the Court is to interpret the words that the Legislature has used. Those words may be ambiguous, but, even if they are, the power and duty of the Court lo travel outside them on a voyage of discovery are strictly limited. " As earlier noticed Lord Simonds and other law Lords in Magor and St. Mel Ion s case were highly critical of the views of Denning, LJ. However, as submitted above, the criticism is more because of the unconventional manner in which the rule of construction was stated by him. In this connection it is pertinent to remember that although a Court cannot supply a real casus omissus it is equally clear that it should not so interpret a statute as to create a casus omissus when there is really none. " ( 21 ) IN Hameedia Hardware Stores v. B. Mohan Lai Sowcar, AIR 1988 SC 1060 , the rule of addition of word had been held to be permissible in the following words:"we are of the view that having regard to the pattern in which clause (a) of subsection (3) of Section 10 of the Act is enacted and also the context, the words if the land required it for his own use or for the use of any member of his family which are found in sub-clause (ii) of Section 10 (3) (a) of the Act have to be read also into sub- clause (iii) of Section 10 (3) (a) of the Act. Sub-clauses (ii) and (iii) both deal with the non-residential buildings. Sub-clauses (ii) and (iii) both deal with the non-residential buildings. They could have been enacted as one sub-clause by adding a conjunction and between the said two sub-clauses, in which event the clause would have read thus: in case it is a non- residential building which is used for the purpose of keeping a vehicle or adapted for such use. If the landlord required it for his. own use or for the use of any member of his family and if he or any member of his family is not occupying any such building in the city, town or village concerned which is his own; and in case it is any other non- residential building, if the landlord or member of his family is carrying on, a non-residential building in the city, town or village concerned which is his own. if the two sub-clauses are not so read, it would lead to an absurd result. " ( 22 ) THE Division Bench of Calcutta high Court in Anemia Kumar Bej (supra), while considering the words "written test" and oral interview occurring in Rule 9 of the West Bengal Recruitment and leave of teachers in Primary Schools Rules, in the light of the doctrine of purposive construction observed:"in this case also unless it is held that the word written test would read with the word "oral interview", the rules cannot be given full effect. In that situation it must be held that the word written test/oral interview has been used in disjunctive manner particularly in view of the fact that no separate marks had been allotted therefor which leads to the conclusion that the same was meant to be conjunctive in nature. " ( 23 ) THERE is another aspect of the matter, which cannot he lost sight of. From the minutes of the meeting dated 18-4-1996 it appears that the committee did not agree to give cross promotions to Trained Graduate teachers as Post-Graduate Teachers. In the instant case, the writ petitioner was appointed as Trained Graduate Teacher in bio-Sciences in the year 1985. She obtained her P. G. qualification in English as private candidate. She, as noticed hereinbefore, sought for promotion as Post-Graduate teacher in English, although she had the requisite qualification in Bio-Sciences. In s. Nagendramma (supra), however, the facts were absolutely different. She was appointed as Trained Graduate Teacher in biological Science on 15-12-1989. She obtained her P. G. qualification in English as private candidate. She, as noticed hereinbefore, sought for promotion as Post-Graduate teacher in English, although she had the requisite qualification in Bio-Sciences. In s. Nagendramma (supra), however, the facts were absolutely different. She was appointed as Trained Graduate Teacher in biological Science on 15-12-1989. She also possessed B. Ed. , qualification. She had the necessary qualifications of M. Sc. , in chemistry having secured 52% marks and B. Ed. , having secured 69% marks. She, as noticed hereinbefore, had been teaching Chemistry for Intermediate class for two years. She therefore, was not given any cross promotion from Trained graduate Teacher as Post-Graduate Teacher, but she was granted relief as she had been teaching science subjects only. Such is not the case with the writ petitioners herein. ( 24 ) FOR the reasons aforementioned, we are of the opinion that the decision of the Division Bench in S. Nagendramma (supra) does not create any binding precedent, whereas the decision in giridhar Kishore (supra) does. Furthermore, the points, which fell for consideration in s. Nagendramma (supra), did not fall for consideration herein. It is now well-settled principle of law that the decision is an authority for what it decides and not what can logically be deduced therefrom [see: Jaya Sen v. Sujit Kr. Sarkar, 2000 (1) ilraandn 145]. It is also well settled principle of law that the decision is not a binding precedent on a point, which was not argued [see: Mittal Engineering Works (?) ltd. v. Collector of Central Excise, (1997) i SCC 203]. ( 25 ) FOR the reasons aforementioned, the impugned judgements cannot be sustained and are set aside. The writ appeals are allowed and there will be no order as to costs.