Civil Rule No.375 of 1990 and Civil Rule No.774 of 1990, both the Civil Rules raise the common question of law and facts and as such they are taken up for hearing together. 2. The prayers made in the writ applications are : (i) To adjudge and declare as illegal, null and void Rule 12 of the Assam Agricultural Engineering Services Rules, 1983; and (ii) Direction to respondents not to give effect to the Rule 12 in the matter of giving promotion to the post of Executive Engineer and Superintending Engineer of the Agriculture Department of the Government of Assam. 3. The brief facts are as follows: In Civil Rule No.375 of 1990 the petitioner Nawab Amanullah obtained Diploma in Civil Engineering in the year 1963. He joined as Subordinate Engineer (R&B) Wing on 24.6.63 and he confirmed with effect from 3.3.79. It is also stated that the petitioner was offered an appointment in Bongaigaon Refinery in the post of Junior Civil Engineer. In January, 1978 there was an advertisement for filling up two posts of Assistant Agricultural (Civil) Engineer with requisite qualification. At that time there was no service rules for Assam Engineering Service. The petitioner applied for the post and he was appointed on 30th July, 1979. The petitioner served as Assistant Agricultural Engineer in various places and subsequently appointed to the post of Sub Divisional Agricultural Engineer in the year 1984. In September, 1991 the provisional Gradation List was published and the name of the petitioner appeared at serial No. 13 and earlier to it another Gradation List was published wherein the petitioner's name appeared in serial No. 17 and that of respondent Nos.5, 6, 7 in serial Nos.22,23 and 24. The respondent Nos.5,6 and 7 joined as Assistant Agricultural Engineer subsequent to the petitioner. The objections were raised regarding the two Gradation Lists. Subsequently, respondent Nos.5, 6 and 7 were promoted to the post of Executive Engineer. The Assam Agricultural Engineering Services Rules, 1983 came into force on 7th of June, 1983. The relevant Rule 12 provides for method of recruitment to Class I by promotion. The rule stipulates that for promotion to the post of Superintending Engineer and also to the cadre of Executive Engineer an officer must have the minimum qualification of Degree in Civil Engineer in Agricultural or Mechanical. The relevant Rule 12 provides for method of recruitment to Class I by promotion. The rule stipulates that for promotion to the post of Superintending Engineer and also to the cadre of Executive Engineer an officer must have the minimum qualification of Degree in Civil Engineer in Agricultural or Mechanical. Thus by the said rule the scope of promotion of the persons in the cadre of the petitioner was blocked. Even though they had the other requisites and qualifications. The Diploma Engineers Services Association represented the matter to the Agricultural Protection Commissioner for modification of Rule 12 so as to give promotional scope to the Diploma holders to the Grade I post. The Commissioner communicated to the Government that since Diploma holders in other departments like PWD, Flood Control are at par that Degree holders in matter of promotion to the higher level, the same may be examined by the Government with regard to the promotional scope for Diploma holders in Agricultural Department. As a matter of fact in 1986 the Commissioner made suggestion and course of action to be adopted by the Govt. for this purpose. But nothing was done. The action of the respondents in not amending Rule 12 is violative of the right of the petitioners. Rule 12 leads to stagnation. The promotion of respondent Nos.5, 6 and 7 are also challenged for irregularity and for not complying with the mandatory rules under Rules 13, 14 and 15 of the aforesaid Rules. It is submitted that hostile discrimination has been meted out to the petitioner. 4. Civil Rule No.744 of 1990 has been filed by 6 persons all of them are Diploma holders and all are Sub Divisional Agricultural Engineers and they have challenged the legality and validity of Rule 12 (3) (a) of the aforesaid Rules as well as the promotion of respondent Nos.3, 4 and 5 in the Civil Rule (respondent Nos.5,6 and 7 in other Civil Rule). The other facts are almost the same. 5. Before we proceed further let us have a look at Rules 12,13,14 and 15 of the Rules 1983. Rules 11 and 12 are quoted below: xxxx  xxxxx xxxx Rule 13 of the Rules provides the general procedure for promotion. Rule 14 provides for special procedure for promotion. The other facts are almost the same. 5. Before we proceed further let us have a look at Rules 12,13,14 and 15 of the Rules 1983. Rules 11 and 12 are quoted below: xxxx  xxxxx xxxx Rule 13 of the Rules provides the general procedure for promotion. Rule 14 provides for special procedure for promotion. Rule 15 provides for Selection Board: For the disposal of these two writ applications it is not necessary to quote these Rules and that aspect to the matter shall be dealt with in the later part of the judgment. 6. An affidavit-in-opposition has been filed on behalf of the respondents. In paragraph 8 of the affidavit-in-opposition it is stated, inter alia, as follows : xxxx  xxxxx xxxx 7. Regarding promotion of the respondents it is stated that the Selection Board was duly constituted under Rule 15 (1) of the Rules and the Selection Board considered all the eligible candidates in accordance with the relevant rules after complying with the provision contained in Rule 13 and thereafter the promotion was made. 8. In paragraph 29 it is stated as follows : xxxx  xxxxx xxxx 9. It is also stated in the affidavit-in-opposition that the respondents underwent Government training IP different courses from time to time and they are better qualified to be promoted. 10. I have heard Shri AM Mazumdar, learned Advocate for the petitioners and Shri DN Chowdhury, learned Advocate for the private respondents and Shri DP Chaliha, the learned Government Advocate for the Government 11. Shri Mazumdar submits as follows : That Rule 12 are discriminatory, unreasonable, unfair and unjust and as such liable to be struck down. (ii) That the denial of promotion to the petitioners and persons similarly situated is a case of hostile discrimination and it also attracts the doctrine of promissory estoppel. (iii) That Rule 12 is violative of Article 14 and 16 of the Constitution of India. (iv) That among similarly and equally placed persons Rule 12 created two distinct classes in respect of their encadrement and as such the Rule is ultra vires, illegal and void. (v) That the Diploma holders and the Degree holders constituted a single cadre at the point of entry and as such at the time of promotion two cadres cannot be created giving undue benefit to the Degree holders. (v) That the Diploma holders and the Degree holders constituted a single cadre at the point of entry and as such at the time of promotion two cadres cannot be created giving undue benefit to the Degree holders. In this connection Shri Mazumdar draws my attention to other similar Rules in the other Departments, that is, in the Department of Assam Engineering (Irrigation Department) Service Rules, 1978 where provision for promotion have been made in case of Diploma holders and the Diploma holders can occupy the highest position in the Department. Shri Mazumdar submits that those Departments are more important Departments and if in those Departments the Diploma holders can occupy the highest position by promotion it is unconceivable to understand as to why the Dipoma holders are being deprived from occupying that position in this particular Department. Shri Mazumdar further argues that the Commissioner made necessary recommendation to give promotional benefits to the persons like the petitioners and in this connection he draws my attention to Memo dated 16.5.86 which is quoted below : xxxx  xxxxx xxxx Even the Director of Agricultural in September, 1986 wrote as follows : xxxx  xxxxx xxxx 12. Shri Mazumdar in support of this contention relied on the following decisions : (i) 1991 (1) GLJ 273 (Shri Jatish Chandra Bhartacharjee vs. State of Assam & others). That was a case regarding promotion under the Assam Forest Service (Class I), 1942 Rules. On November, 26, 1979 the State Government promoted 3 direct recruits ignoring the petitioners who are senior to all the three direct recruits. There was a circular and Minutes regarding the promotion and that Circular and Minutes were utilised for promoting these three persons out of turn and this was challenged. The question which arose for decision in that case was formality by the Court as fallows: "In the instant case we are to decide the scope and ambit of the impugned Circular whether the Circular supplemented the gaps in 1942 Rules or whether Circular in tenure is contrary to Rule 4 of 1942 Rules. The question which arose for decision in that case was formality by the Court as fallows: "In the instant case we are to decide the scope and ambit of the impugned Circular whether the Circular supplemented the gaps in 1942 Rules or whether Circular in tenure is contrary to Rule 4 of 1942 Rules. We are of the view and hold the Circular is contrary to the statutory rules and to show it is contrary to statutory rules no much effort is needed as facts in the instant case are proved, positive to bring out the result." Shri Mazumdar strongly relies on the observation in the judgment which is quoted below: "It is seen the circular is inconsistent with statutory Rules 4 and 15 of the 1942 Rules. It is one of the cardinal principles of our rule of law the executive orders cannot amend statutory rules. One feature of service law often propounded in the cases is stated in (1980) 4 SCC 562 , SL Sachdev vs. Union of India. The ratio of the decision propounds the principle that when from various sources officers are recruited like ACFs who are recruited from subordinate services and AFCs are recruited direct all these distinctions (enterior to appointment) are obliterated on or after appointment to the cadre of AFCs. To recognise the enterior distinction like direct recruit or promotee Act for further promotions violate the principle of equally enshrined in Article 14 of the Constitution of India." This case does not help the petitioner inasmuch as in our case it is the Rule which creates a bar for the petitioner. In the case cited it was the Circular which created the right in favour of the direct recruits to be promoted first and that was found not to be followed by this Court. (ii) (1989) 2 SCC 344 (N. Abdul Basheer & others vs. KK Karunakaran & others). That was a case where a writ application was filed by non-graduate Excise Inspector alleging that the maintenance to Special Rule 2 and the aforesaid Rule violates the Article 14 and 16 of the Constitution inasmuch as an invidious discrimination has been made between graduate and non-graduate by prescribing a ratio between them in the matter of promotion from the post of Excise Preventive Officer to that of Second Grade Excise Inspector. By the amendment Rules the preference was shown to graduates and they were given more weightage in the matter of promotion. The Supreme Court held, inter alia, as follows : "Ordinarily it is for the Government to decide upon the consideration which in its judgment, should underlie a policy to be formulated by it. But if the considerations are such as prove to be of no relevant to the object of the measure framed by the Government it is always open to the Court to strike down the differentiation as being violative of Article 14 and 16. In the present case the conditions of employment and the incidents of service recognise no distinction between graduate and non- graduate officer and for all material purposes they are effectively treated as equivalent. The history of the evolution of the Karela Excise and Prohibition Subordinate Service has shown no uniformity either in approach or in object The conditions pertaining to the service, and respecting which the constitution of the service varied from time to time, showed fluctuations: A consistent or coherent policy in favour of graduates was absent. This is not a case where the cadre of officers was kept in two separate divisions. It was a single cadre, and they were all equal members of it. There is no evidence that graduate Preventive Officers enjoyed higher pay than non-graduate Preventive Officers. The High Court has noted that the nature of the duties of Preventive Officers whether graduate or non-graduate was identical, and both were put to field works. Non-graduate Preventive Officers were regarded as competent as graduate Preventive Officers. There is no evidence of any special responsibility being vested in graduate Preventive Officers. Once they were promoted as Excise Inspectors, there was no distinction between graduate and non-graduate Excise Inspectors. Therefore the prescription of a ratio dividing the quota of promotion between graduate Preventive Officers and non-graduate Preventive Officers is invalid on the ground that it violates Article 14 and 16. In A this view there is also no substance in the contention that the ratio between graduates and non-graduates is supportable on the ground that the recognition of graduation is recognition of merit, and that more merit in the post of Excise Inspectors would be conducive to better administrative efficiency." And in arriving at this decision the Supreme Court relied on a number of cases. It is argued by Shri Mazumdar relying on this decision that the petitioners and the graduate Engineers were doing the job of Assistant Agricultural Engineer and it was a common cadre. So at the time of promotion no discrimination can be made and as such the rule creating the right of promotion in favour of the graduate Engineers only is liable to be struck down. 13. It is further argued that by making the rule the promotional prospect of the petitioner has been blocked for all time to come and it cannot be done. That there cannot be total reservation in the matter of promotion to the posts of Executive Engineer and Superintending Engineer in the case of Degree holders only. That this rule is based on no reasonable classification and that there is no intelligible basis and or criteria for making such a classification in respect of promotion to the post of Executive Engineer and Superintending Engineer even after their joint encadrement in the cadre of Assistant Agricultural Engineer, Sub-Divisional Agricultural Engineer. That there is no nexus with the object sought to be achieved and the said policy of promotion is discriminatory and violative of Article 14 and 16 of the Constitution of India. On the other hand Shri Chowdhury the learned Advocate appearing for the private respondents relying on the following decisions submits that this rule is valid and question of striking out it do not arise. In support of his submissions Shri Chowdhury places reliance on the following decisions : (i) (1974) 1 SCC 19 (The State'of Jammu and Kashmir vs. Sri Triloki Nath Khosa & others). That was a case where the Diploma holders were serving in the different branches of the State of Jammu and Kashmir as Assistant Engineer till promotion from the Superintending Subordinate Engineering Service. Their conditions of service were then governed by the relevant Rules of 1939 under which graduate in Civil Engineering were alone eligible for direct recruitment 5 as Assistant Engineer. Only departmental promotions could be made from amongst the Diploma holders and that too if they had put in 5 years of service in the cadre of Supervisors. Then come to the Jammu and Kashmir Engineering (Gazetted) Service Recruitment Rules, 1970 superseding the old rule on the subject. Only departmental promotions could be made from amongst the Diploma holders and that too if they had put in 5 years of service in the cadre of Supervisors. Then come to the Jammu and Kashmir Engineering (Gazetted) Service Recruitment Rules, 1970 superseding the old rule on the subject. As regards promotion to the post of Executive Engineers and to those only it was provided therein that only those Assistant Engineers would be eligible for promotion, possesses a betterment degree in the Engineering OF had the qualification of AMIE and those who were put in atleast 7 years of service. This rule was impugned by the Diploma holders on the ground that this rule deprive them equal opportunity in the matter of promotion and is violative of Article 14 and 16 of the Constitution of India. It was further contended that it was not competent to the Government to change the service condition unilaterally to the disadvantage of its employees so as to deprive them of their vested right of promotion by giving retrospective effect to the rules. The majority judgment held inter alia as follows : "Held : Per Ray, CJ Palekar, Chandrchud, Bhagwati and Krishna lyer, JJ (i) It is wrong to characterise the operation of a service rule as retrospective for the reason that it applied to existing employees. A rule which classifies such employees for promotion purposes undoubtedly operates on those who entered service before the framing of the rule, but it operates in future, in the sense that it governs the future right of promotion of those who are already in service. The rule cannot first be assumed to be retrospective and then be struck down for the reason that it violates the guarantee of equal opportunity by extending its arms over the past, (ii) It is well settled that though employment under the Government like that under any other master may have a constractual origin, the Government servant acquires a 'status' on appointment to his office. As a result, his rights and obligations are liable to be determined under statutory or constitutional authority which, for its exercise, requires no reciprocal consent. As a result, his rights and obligations are liable to be determined under statutory or constitutional authority which, for its exercise, requires no reciprocal consent. The Government can alter the terms and conditions of some of its employees unilaterally and though in modern times consensus in matters relating to public services is often attempted to be achieved, consent is not a precondition of the validity of rules of service, the contractual origin of the service nothwithstanding. (iii) Where a party seeks to impeach the validity of a rule made by a competent authority on the ground that the rules offend Article 14 the burden is on him to plead and prove the infirmity. There is always a presumption in favour of the constitutionality of an enactment and the burden is upon him who attacks it to show that there has been a clear transgression of the constitutional principles. A rule cannot be struck down as discriminatory on any a priori reasoning. The burden thus is on the respondents to set out facts necessary to sustain the plea of discrimination and to adduce cogent and convincing evidence to prove those facts for there is a presumption that every factor which is relevant or material has been taken into account in formulating the classification, between degree holders and diploma holders. Unless the classification is unjust on the face of it, the onus lies upon the party attacking the classification to show by pleading the necessary material before the Court that the said classification is unreasonable and violative of Article 16. Thus it is no part of the appellants' burden to justify the classification or to establish its constitutionality. Formal education may not always produce excelence but a classification founded on variant educational qualifications is, for purposes of promotion to the post of Executive Engineer, to say the least, not unjust on the face of it and the onus therefore cannot shift from where it originally lay. (iv) Classification is primarily for the Legislature or for the statutory authority charged with the duty of framing the terms and conditions of service; and if, looked at from the stand point of the authority making it, the classification is found to rest on a reasonable basis, it has to be upheld. (v) Discrimination is the essence of classification and does violence to the constitutional guarantee of equality only if it rests on an unreasonable basis. (v) Discrimination is the essence of classification and does violence to the constitutional guarantee of equality only if it rests on an unreasonable basis. It was therefore, incumbent on the respondents to plead and show that the classification of Assistant Engineers into those who hold diploma and those who hold degree is unreasonable and bears no rational nexus with its purported object. Omission to furnish the necessary particulars has been construed by the Supreme Court as indicating that the plea of unlawful discrimination had no basis. (vi) Article 16 of the Constitution which ensures to all citizens equality of opportunity in matters relating to employment is but an instance or incident of the guarantee of equality contained in Article 14. The concept of equal opportunity undoubtedly permeats the whole spectum of an individual's employment. But the concept of equality has an inherent limitation arising from the very nature of the constitutional guarantee. Equality is for equals. Since the constitutional code of equality and equal opportunity is a charter for equals, equality of opportunity in matters of promotion means an equal promotional opportunity for persons who fall, substantially, within the same class. A classification of employees can therefore be made for first identifying and then distinguishing members of one class from those of another. Classification, however, is fraught with the danger that it may produce artificial inequalities and therefore, the right to classify is hedged in with salient restraints. Classification must be truely founded on substantial differences which distinguish person grouped together from those left out of the group and such differential attributes must bear a just and rational relation to the object sought to be achieved. Judicial scrutiny can therefore extend only to the consideration whether the classification rests on a reasonable basis and whether it bears nexus with the object in view. It cannot extend to embarking upon a nice or mathematical evaluation of the basis of the classification for were such an inquiry permissible it would be to the Court to substitute their own judgment for that of the legislature of the rule making authority on the need to classify or the desirability of achieving a particular object. (viii) One has always to bear in mind the facts arid circumstances of the case in order to judge the validity of a classification. (viii) One has always to bear in mind the facts arid circumstances of the case in order to judge the validity of a classification. (ix) All that Roshan Lal's case laws down is that direct recruits and promotees loss their birth marks on fusion into a common stream of service and they cannot thereafter be treated differently by reference to the consideration that they were recruited from different sources. Roshan Lal's case is thus no authority for the proposition that it direct recruits and promotees are integrated into one class, they cannot be classified for purposes of promotion on a basis other than the one that they were drawn from different sources. In the instant case, classification rests fairly and squarely on the consideration of education qualifications; graduates alone shall go into the higher post, no matter whether they were appointed as Assistant Engineers directly or by promotion. The discrimination, therefore, is not in relation to the source of recruitment as in Roshan Lal's case. The ratio of Roshan Lal' s case can at best be an impediment in favouring persons drawn from one source as against those drawn from another for the reason merely that they are drawn from different sources. (x) It is often impossible or at any rate inexpedient to reach and remedy all forms of evil, wherever present. Reform must being somewhere if it has to begin at all and therefore the administrator who has nice and complex problems to solve must be allowed the freedom to proceed tentatively. (xi) Thus though persons appointed directly and by promotion were integrated into a common class of Assistant Engineers, they could, for purposes of promotion to the cadre of Executive Engineer be classified on the basis of educational qualifications. The rule providing that graduates shall be eligible for such promotion to the exclusion of diploma holders does not violate Article 14 and 16 of the Constitution and must be upheld. The differences between the two classes - graduates and diploma holders furnish a reasonable basis for separate treatment and bear a just relation to the purpose of the impugned provision." (ii) (1989) SuppI (1) SCC 116 (Rup Chand Adktkha & others vs. Delhi Development Authority & others). The differences between the two classes - graduates and diploma holders furnish a reasonable basis for separate treatment and bear a just relation to the purpose of the impugned provision." (ii) (1989) SuppI (1) SCC 116 (Rup Chand Adktkha & others vs. Delhi Development Authority & others). That was a case where the Delhi Development Authority made a classification between the Graduate Engineers and Diploma holders for the purpose of promotion and the Supreme Court laid down the law as follows : "Held: State, consistent with the requirements of the promotional posts and in the interest of the efficiency of the service, is not precluded from conferring eligibility on diploma holders conditioning it by other requirements which may as here, include certain quantum of service experience. It cannot be said that the choice of the State was either to recognise diploma holders as 'eligible' for promotion or wholly exclude them as 'not eligible'. If the educational qualification by itself was recognised as conferring eligibility for promotion, then the super imposition of further conditions such as a particular period of service, selectively, on the diploma holders alone to their disadvantage might become discriminatory. This does not prevent the State from formulating a policy which prescribes as an essential part of the conditions for the very eligibility that the candidate must have a particular qualification plus a stipulated quantum of service experience. The graduates and diploma holders were not treated as equal in the matter of eligibility for promotion. The different prescriptions for conditioning eligibility are themselves questioned which need to be decided on the basis whether the discrimination contemplated and brought about in the matter of promotional opportunities between graduates and non-graduates, based on the differences in the equality of their technical qualifications, were relatable to, and justified on the basis of the requirements of the promotional posts. On the basis of the' Vanish Committee' report, the authorities considered the infusion of higher academic and technical quality in the personnel requirements in the relevant cadres of Engineering Services necessary. These are essentially matters of policy. Unless the provision is shown to be arbitrary, capricious, or to being about grossly unfair results, judicial policy should be one of judicial restraint. These are essentially matters of policy. Unless the provision is shown to be arbitrary, capricious, or to being about grossly unfair results, judicial policy should be one of judicial restraint. The prescriptions may be somewhat cumbersome or produce some hardship in their application in some individual cases, but they cannot be struck down as unreasonable, capricious or arbitrary." (iii) (1990) 2 SCC 228 (K. Jagadeesan vs. Union of India & others). That was a case where the rule was framed under Article 309 requiring Engineers qualification for promotion from Mechanical Engineer (Senior) to Director (ME). Consequently a Diploma holders in Engineering who was eligible under the unamended rule became ineligible under the amended rule which was challenged. The Supreme Court held that the amended rule is valid. The Supreme Court further found that merely because it adversely affected the chances of Diploma holders for promotion or his right to be considered for promotion. It was further held that qualification which is to be laid down for a particular post is the function of the Government. It was further held that the recruitment of the graduate degree for Director (Mechanical) under the amended rule is not unreasonable or bad. (iv) AIR 1993 SCI 173 (Shamkant Narayan Deshpande vs. Maharashtra Industrial Development Corporation & another). That also was a case regarding promotion to the post of Superintending Engineer and a qualification was made between the Degree holders and Diploma holders, Executive Engineers and it was further held that classification mentioning some clause on basis of qualification is permissible. It was even held that this classification even can be made by a mere resolution and it was further held that conditions of service can be changed even by executive instruction if that executive instruction does not rather counter to the rule. 14. Shri Mazumdar also placed reliance on the recent decision of the Apex Court in (1994) 6 SCC 282 wherein the Supreme Court has laid down the law as follows : "The following legal propositions emerge regarding educational qualification being a basis of classification relating to promotion in public service : (1) Higher educational qualification is a permissible basis of classification, acceptability of which will depend on the facts and circumstances of each case. (2) Higher educational qualification can be the basis not only for barring promotion, but also for restricting the scope of promotion. (2) Higher educational qualification can be the basis not only for barring promotion, but also for restricting the scope of promotion. (3) Restriction placed cannot however go to the extent of seriously jeopardising the chances of promotion. To decide this, the extent of restriction shall have also to be looked in to ascertain whether it is reasonable. Even if in a case the classification would not be acceptable to the Court in principle, it would, before pronouncing its judgment, bear in mind the historical background. While judging the validity of the classification, the Court shall have to be conscious about the need for maintaining efficiency in service and also whether the required qualification is necessary for the discharge of duties in the higher post. Apart from the aforesaid propositions there are two other determinants viz the all of social justice and importance of education. Court has to see, while examining the provision of the anvil of Article 14 and 16 of the Constitution, whether Article 21 is offended in any way. At the same time it was to be remembered that diploma holders are drawn mainly from poorer families and they are incapable of making the degree grade. The 'Chill Penury' should not,, therefore, be allowed to "repress their noble rage". Social justice would not permit the Court to do so. It may be that social justice is not a fundamental right, social justice being a requirement of directive principles of our Constitution, the same has to be our desidertum in any case." 15. Shri Mazumdar specifically relied on para 22 and 23 are quoted below: "22. The aforesaid shows that higher educational qualification has relevance insofar as the holding of higher promotional post is concerned, in view of the nature of the functions and duties attached to that post. The classification has, therefore, nexus the object to be achieved. This apart, history also supports the differentiation sought to be made by the rule in question. We, therefore, upheld the . classification as valid. 23. The next question to be examined is about the extent of the preference given to the degree holders. At this stage, we may first give our reasons as to why this aspect is amenable to examination. We, therefore, upheld the . classification as valid. 23. The next question to be examined is about the extent of the preference given to the degree holders. At this stage, we may first give our reasons as to why this aspect is amenable to examination. The rule making authority having made a diploma holder eligible for promotion, it follows that a diploma holder does not suffer from such an infirmity as to make totally unfit for holding the higher post. If that is so, question is whether the ratio could be made so inequitable as to mock at the guarantee of equality ? The right which has been conferred by one hand cannot be taken away by another, nor can the right be converted to a husk. It must continue to be a meaningful right. Too much emphasis on higher education may even cause dent to cause of social justice, as it would be the pooper section of the society which would be deprived of its legitimate expectations. The preference given to the degree-holders would, at the same time, give fillip to the desire to receive higher education, as such persons would always be favourably placed as compared to the lesser educated ones. A harmony would this be struck by maintaining reasonableness in the ratio, between the call of social justice and the need for higher education, without in anyway jeopardising the principal object of classification. But then, no particular ratio can be spelt out which would satisfy these requirements, the reasonableness of the ratio shall depend on facts of each case." 16. Shri Mazumdar submits that in this particular case the rule making authority has totally blocked the avenue of promotion of the Diploma holders and these are against the law as laid down by the Supreme Court. 17. Shri Mazumdar submits that in this particular case the rule making authority has totally blocked the avenue of promotion of the Diploma holders and these are against the law as laid down by the Supreme Court. 17. Regarding the submission of Shri Mazumdar it is submitted by Shri Chowdhuty and Shri Chaliha appearing for the Government that this department is a small department and there the number of posts of Executive Engineer and Superintending Engineers are very few and as such these posts are to be manned by better qualified people arid if the scope of promotion be given to Diploma holders this vital post will be manned not by efficient and qualified persons and it was because of this that the rule making authority in their wisdom did not make law for promotional avenue to the Diploma holders beyond the post of Assistant Agricultural Engineer or Sub Divisional Agricultural Engineer and on that count this rule cannot be deemed to be invalid. It is settled that chances of promotion are not condition of service. A rule which merely affects chances of promotion must be regarded as varying condition of service. Regarding declaring rule to be ultra vires the Court should bear in mind that whatever may fairly be regarded as incidental to or consequential upon, those things which the Legislature has authorised should not (unless expression prohibited) to be held'by judicial construction to be ultra vires. 18. Regarding concept of equality as between the members of the same class the question whether the condition of service are the same or not may well arise. If they do not belong to the same class the question of denial of equal opportunity will require serious consideration. The concept of equality can have no existence except with reference to matter which are common as between individuals, between whom equality is claimed. But if the two persons are not equal in all repects the question of applying the doctrine of equality shall not arise. 19. As indicated above promotion is not a question of right nor it can be claimed as a matter of right. The promotion can be regulated by rule which governs the conditions of recruitment, promotion and other things known as service conditions. And if there are statutory rules and if they are not unreasonable, unfair, arbitrary or capricious, the validity of the same can not be questioned. The promotion can be regulated by rule which governs the conditions of recruitment, promotion and other things known as service conditions. And if there are statutory rules and if they are not unreasonable, unfair, arbitrary or capricious, the validity of the same can not be questioned. So multifanious are the activities of the State with the employment of the men for the purpose of these activities has by the very nature of things to be dealt with by the expert and the Court is not competent to scrutinize what will be necessary requirement including qualification fora particular post. As between the members of the same class the question whether the condition of service are the same or not may well arise. If they are not, the question of denial of equal opportunity requires consideration in such cases. The concept of equality can had no existence except with reference to matters which are common as between the individuals, between whom equality is protected or claimed. Equality of opportunity in matters of promotion must mean equality as between members of the same class of employees and not equality between the members of the separate independent classes. 20. In that view of the matter validity as Rule 12 as urged by the petitioner shall fail. 21. The next question is that whether the promotion of respondent Nos.5,6 and 7 were made or not in compliance with Rule 13 and 15 of the Rules. As a matter of fact on this point no argument was advanced by Mr. Mazumdar and I also perused the materials and find that these promotions were made in compliance with the relevant Rules. Accordingly I hold that the promotion of respondent Nos.5, 6 and 7 are valid in the eye of law. Accordingly there is no merit in the writ application and the same is dismissed. 22. Before I part with the record I want to make an observation. By Rule 12 the entire promotional avenue of the Diploma holders have been blocked. I leave it to the wisdom of the authority to give some consideration to this aspect of the matter and make some avenue for the promotion of the Diploma holders, as providing promotional avenue is necessary for better and efficient service and in order to give inducement for better work to the employees. 23. The writ applications accordingly stands rejected. I leave it to the wisdom of the authority to give some consideration to this aspect of the matter and make some avenue for the promotion of the Diploma holders, as providing promotional avenue is necessary for better and efficient service and in order to give inducement for better work to the employees. 23. The writ applications accordingly stands rejected. I leave the parties to bear their own costs.