D. K. SETH, J. The petitioner was commissioned in the Army Education Corps (hereinafter referred to as AEC) through the short Service Commission (Non-Technical) by an order dated 24-4-1973 with effect from 29-4-1973 - for five years in the Army in the rank of Second Lieutenant under the terms and conditions of service as contained in Army Instructions No. ll/s/64. He had undergone training for ten months at the Officers Training School (hereinafter referred to as OTS) at Madras. Subsequently, the petitioner was granted permanent/regular commission in AEC at Indian Military Academy, Deh-radun (hereinafter referred to as IMA ). The fixation of seniority of Short Service Com mission (hereinafter referred to as SSC) Of ficers, commissioned permanently in the Army is regulated by Army Instruction-AI-3/s/70 as amended by Amendment No. AI-93/73, dated 28-7-1973. The said instruc tions in clause (v) provides that the seniority of SSC Officers would be granted on anti- dated equivalent to their full pay commis sioned service as SSC Officer less period of shortfall in their training of the training prescribed for grant of SSC from that prescribed for the particular type of per manent Commission entry at the IMA. Ac cording to the petitioner the training period of direct recruit officer commissioned in AEC at IMA is 12 months and he is granted seniority from the date of his completion of such training. Therefore, the petitioner is entitled to the grant of seniority from the date of his full pay commission service in SSC less by two months, being difference of the training period of OTS and AEC at IMA. Whereas while fixing the seniority one year two months instead of two months was deducted from the period of full pay com mission service in SSC Being aggrieved the petitioner made an application to the Military Secretary, Headquarter, through the Commanding Officer (Annexure-1 to the petition ). The Commanding Officer while forwarding the said application recommended that seniority due to the petitioner rightfully be restored (Annexure-2 to the petition ). By a letter dated 29-2-1988 (Annexure-3) the petitioner was in formed about the rejection of his aforesaid application which was a non- statutory com plaint, on the ground that the petitioners entry in SSC was for non-technical stream of OTS, at Madras. By a letter dated 29-2-1988 (Annexure-3) the petitioner was in formed about the rejection of his aforesaid application which was a non- statutory com plaint, on the ground that the petitioners entry in SSC was for non-technical stream of OTS, at Madras. Therefore for the purposes of fixation of his seniority he was to be compared with the non-technical can didates granted permanent commission at IMA, who were required to under-go two years training and, therefore, difference of the training period, being one year and two months, was deducted while fixing the petitioners seniority, from the period of full Pay Commission in SSC Aggrieved thereby the petitioner preferred a statutory com plaint on 27-6-1988 to the Central Govern ment through proper channel. While for warding the statutory complaint the Presi dent, 19-Service Selection Board, Al lahabad (SSB) endorsed the recommenda tion that the petitioners contention ap pears to be genuine (Annexure-5 ). By an order dated 11-7-1989 (Annexure- SAl) the petitioners statutory complaint was rejected by the Central Government. The information about the rejection of statutory complaint was intimated to the petitioner on 29-12-1989 (Annexure-6 to the writ peti tion and annexure-SA 1 to the Supplemen tary affidavit. ). The petitioner was facilitated with a copy of the said order dated 11-7-1989 only through the said letter dated 24-6-1990, after the petitioner had sent three letters dated 29-1-1990, 15-2-1990 and 21-3-1990 respectively, requiring copy of the said order. It is this order (An-nexure-SA2) which is the subject-matter of challenge in the. present proceedings filed by the petitioner, who prayed for quashing of the said order contained in annexure- SAz and fixation of his seniority from 29-6-1973 instead of 26-6-1974. 2. In the counter-affidavit the respon dents had contended that the petitioner having commissioned in AECas SSC (Non technical) in the month of April 1973 , had undergone ten months training at OTS Madras. Similar category of Officers in ducted into IMA, as permanent Commis sioned Officers, are required to undergo training at IMA for two years before grant ing commission. Therefore, the short fall of the training period applicable to regular officers inducted into Army under the same non-technical stream was deducted from the period of full pay commission of service of the petitioner is SSC in accordance with the Army Instructions number 3/s/70 as amended by Army Instructions number 93/73. Therefore, the short fall of the training period applicable to regular officers inducted into Army under the same non-technical stream was deducted from the period of full pay commission of service of the petitioner is SSC in accordance with the Army Instructions number 3/s/70 as amended by Army Instructions number 93/73. Since the petitioners entry was in non-technical stream, therefore, while granting permanent commission, he is to be treated in the same non-technical stream, for which two years training is prescribed and accordingly one year and two months is deducted as short fall of the training period while fixing seniority. The benefit of train ing period of respect of direct entry (per manent commission) through AEC Of ficers, therefore, cannot be extended to the petitioner. Thus there is no illegality in rejecting the non-statutory complaint by order, dated 29-2-1988 (Annexure-3) or in the order dated 11- 7-1989 (Annexure-SA2 ). Therefore, present writ petition should be dismissed. 3. In the rejoinder-affidavit the petitioner has repeated the statements made in the writ petition while elucidating and elaborating the same further. 4. Sri Amar Saran, learned counsel ap pearing on behalf of the petitioner con tended that the fixation of seniority, in the facts and circumstances of the case, and in view of the Army Instructions, cannot be sustained in law. The petitioner cannot be treated for the purposes of seniority at par with the other officers, granted permanent commission at IMA in non-technical stream, since the petitioner was inducted in AEC which through clubbed with the non technical officers, but the training period of the direct recruits in AEC is one year. Therefore the petitioner has to be treated at par with AEC candidates. 5. Sri Sushil Harkauli, learned counsel appearing on behalf of the respondents, on the other hand, contends that the entry in a particular stream is the determining factor. Since the petitioners entry was in non-tech nical stream in SSC he is to be treated at par with the non-technical stream granted permanent commission at IMA According to him unless it is so determined the petitioner would become senior to his batch-mates, who were inducted at IMA in the branches other than AEC. Inasmuch as all the batch-mate of the petitioner inducted at IMA were given seniority after deducting one year two months from full pay commission service in SSC. Inasmuch as all the batch-mate of the petitioner inducted at IMA were given seniority after deducting one year two months from full pay commission service in SSC. Since the petitioner was the only per son, who joined AEC at IMA from SSC and there having been no waste in AEC no fur ther induction in AEC is made, therefore, there can not be any separate kind of treat ment for the petitioner from those of his batch- mates. 6. It is the case of the respondents that in terms of the Army Instruction AI-3/s/70 as amended vide Al- 93/73 the petitioners seniority is to be fixed after deducting the said short fall period of one year two months from his full pay commissioned service in SSC. 7. However, the learned counsel for the respondents could not show anything which specifies that once entry is non-tech nical stream in SSC the same is final and can not be changed when inducted at IMA on permanent commission. On the other hand he very fairly conceded that he is not aware as to the existence of any such instruction. According to him while the batch-mates of the petitioner had their seniority fixed as on 29-6-1974, if the petitioners contention is accepted, his seniority would have to be fixed as on 29th June 1973. 8. In para-4 of the counter-affidavit, it has been stated, "that the petitioner was commissioned in AEC as short service (non- technical) in the month of April 1973. "admittedly, the petitioner was inducted at IMA in AEC on permanent commission. The petitioner in paragraph-9 of the peti tion has quoted Army Instruction No. AI-105/61 so far as it is relevant for AEC. In para-11 of the counter-affidavit the respon dents have admitted that the said Army In struction has been correctly reproduced in para-9 of the writ petition. The direct recruits granted permanent commission in AEC are governed by the said Army Instruc tions. 9. In order to appreciate the rival con tentions, it is necessary to refer to Army Instructions No. AI- 105/61 which runs as under: "1. The direct recruits granted permanent commission in AEC are governed by the said Army Instruc tions. 9. In order to appreciate the rival con tentions, it is necessary to refer to Army Instructions No. AI- 105/61 which runs as under: "1. A certain number of permanent regular commissions will be granted to Engineering Graduates in Corps of Engineers, Signals and Electrical and Mechanical Engineers and to Graduates in Agriculture in the Military Farms Services and Art/science Graduates in AEC/asc (Food Inspection Organization) after a short course of training at the Indian Military Academy, Dehradun. ************ (b) Age-limits-A candidate to be eligible must not have passed his 27th birthday and must not be below 20 years of age on the 1st day of the month of the commencement of the course which will be notified sufficiently in advance. Age-limits for AEC candidates will be 23-27 years. ************************ (v) Army Education Corps (a) An M-A. /m. Sc degree in 1st or 2nd Division of a recognised University plus a de gree/diploma in teaching; Or (b) An M-A/ M. Sc degree in 1st or 2nd Division of a recognised University with at least 2-3 years experience of teaching in a High/higher Secondary School, College or University. 2. Method of Selection- (a) Application on the prescribed forms will be submitted to the AGs branch Rtg. 6 (SP) (b) Candidates will be required to appear for an interview by SSB. 3. Training-selected candidates will be re quired to undergo a course of Training for a period of about 12 months at the Indian Military Academy, Dehradun. The entry into the course will be half yearly w. e. f. January 1961. 4. Grant of Commission-Commissions will be granted in the rank of 2/lt. only on successful completion. of training at the Indian Military Academy, Commissions will be dated from the date on which the training at the Academy suc cessfully completed. " 10. It is apparent from the above Army Instructions that a candidate selected for AEC at IMA recruited directly are required to undergo Training for a period of twelve months and commission is granted in the rank of Second Lieutenant on successful completion of the training at IMA from the date of completion of training. " 10. It is apparent from the above Army Instructions that a candidate selected for AEC at IMA recruited directly are required to undergo Training for a period of twelve months and commission is granted in the rank of Second Lieutenant on successful completion of the training at IMA from the date of completion of training. Therefore, a directly recruited candidate commissioned in AEC at IMA would be entitled to get his seniority fixed only after deduction of 12 months from the date of his entry. Admit tedly, the petitioner had undergone training of ten months at OTS Madras. Therefore, there is short fall of two months in respect of the period of training between a direct recruit and an SSC officer commissioned in AEC. 11. It is necessary to refer to Army Instruction No. AI-3/s/70. Relevant portion whereof is re-produced below: "56-AI-3/s/70 regarding grant of permanent Commission Service to short service commis sioned officers is amended as under: (Amendment No. 3) Clause (b) is reconsidered as under: (b) For the purpose of seniority and promo tion (both substantive and acting) officers will be granted an ante dated equivalent to their full pay commissioned service as a short Service Commis sioned Officer less the period of short fall in their training to be arrived at by deducting the period of training prescribed for grant of Short Service Commission from that prescribed for a particular type of permanent Commission entry at the In dian Military Academy. " 12. A plain reading of clause (b) of the relevant Army Instruction reveals, seniority of SSC officers ought to be fixed at an ante date equivalent to their full pay commis sioned service at SSC less the period of short fall in their training being difference of the period of training, under-gone in SSC from that prescribed for a particular type of per manent commission entry at IMA. There fore, it is plain and simple that the said provision does not prescribe that the period of short fall in training is to be calculated from the period of-training of permanent Commission at the IMA. Neither the in struction prescribes that entry in SSC would be governing factor for calculating the short fall of the training period. Our attention has not been drawn to any such instructions. Neither the in struction prescribes that entry in SSC would be governing factor for calculating the short fall of the training period. Our attention has not been drawn to any such instructions. On the other hand it clearly specified the terms when it uses the phrase by deducting the period of training prescribed for grant of Short Service Commission from that prescribed for a particular type of per manent commission entered at IMA. " The period of training at OTS Madras has to be deducted from the prescribed period of training for a particular type of permanent commission entered at IMA. As we have found from AI-105/. 62 that AEC is a dif ferent service like other different services namely Corps of Engineers, Signals and Electrical and Mechanical Engineers and in the Military Farms Service, AEC/ssc being the short course of training at IMA. The training has been prescribed in para-3 of the said Army Instruction No. AI-105/61, is for a period of 12 months. The commission is granted in terms of para-4 thereof on the date on which training is successfully com pleted. Therefore, a direct recruit in AEC at IMA would be entitled to fixation of his seniority from the date of successfully com pletion of the training, meaning thereby that there would be a deduction of the period of 12 months from the date of his entry at IMA. Whereas if the contention, as advanced on behalf of respondents, is ac cepted, in that event a person inducted at IMA from SSC would suffer a loss of one year more than the direct recruit while having his seniority fixed. It is not disputed that the petitioners entry in SSC was in AEC and he was inducted at IMA in AEC being the same stream. 13. Learned counsel for the respon dents has not been able to indicate or draw our attention to any Instructions, Rules or Regulation by which AEC can be specified as non-technical or technical. 14. But the facts remained that the training period required for commission in AEC is fixed at 12 months. Therefore a person inducted in AEC from SSC cannot be discriminated upon with those who had entered through direct recruitment process in the matter of calculation of period of training for the purposes of clause (b) of Army Instruction No. AI-3/s/70 as amended by AI-93/73. Therefore a person inducted in AEC from SSC cannot be discriminated upon with those who had entered through direct recruitment process in the matter of calculation of period of training for the purposes of clause (b) of Army Instruction No. AI-3/s/70 as amended by AI-93/73. Admittedly, AEC is a par ticular type of entry. Therefore, the period prescribed for training in AEC is the period from which deduction of the period of training at OTS is to be deducted. While fixation of seniority of a person entering in a par ticular type of entry can not be dependent upon the training period prescribed for another type of entry though, however, both may be non-technical. It is apparent that the description of non- technical can not be the criterion. It is a particular type of entry in permanent commission, is the criterion, which is determining factor for deduction of the period of training undergone in SSC, as contemplated in Clause (b) of AI/3/s/70 as amended by the Army Instruction No. AI/93/73. The batch-mates of the petitioner having entered in different type can not be treated to be in the same class or classifica tion. Article 14 of the Constitution does not prohibit classification altogether. The clas sification must be backed by rationale. The classification of AEC stands altogether dif ferent from the other entries which is ap parent from clause (b) of Army Instruction number AI-105/61 prescribing the age-limit and item (v) prescribing the qualification. In-as much as the age-limit for AEC can didate is 23-27 years while that of other entries are 20-27 years. Specific qualifica tion M. A. /m. Mc. degree in 1st or IInd Division of a recognised University and De gree/diploma in teaching or M. A. /m. Sc degree in 1st or IInd Division of a recognised University with atleast 2-3 years experience of teaching in High/higher Secondary School, College or University, has been fixed, which is much higher than other can didates. Admittedly, two years anti-date seniority is given from the date of successful completion of training to a Engineering graduate entering into other specialised ser vice at IMA. 15. Therefore, different criterion are in existence for different type of entry. Clas sification does not depend on the year of entry, but on the particular type of service in which entry is made. 15. Therefore, different criterion are in existence for different type of entry. Clas sification does not depend on the year of entry, but on the particular type of service in which entry is made. It is apparent that though the entry is made in different service at the same time but there are different period of training for different services and different criterion in fixation of seniority in different types. Therefore the classification is acknowledged, accepted and recognised at IMA for different types of entry and different type of seniority is being granted to different type of entry. If the batch-mates of the petitioner are inducted in some other branches of stream the same can never be governing factor for determining the seniority of the petitioner. The seniority is to be fixed on the basis of instructions governing service. In the present case the petitioner entry was in AEC in SSC. When inducted in permanent commission in AEC the rules governing AEC candidates in per manent Commission would be applicable in his case. It cannot be said that because the petitioner was described as non-technical in SSC, therefore, the rule governing AEC candidates would be inapplicable in his case simply because he was described as non technical. 16. The order dated 29-2-1988 did not specify anything as to on which basis it was decided that the petitioner was required to undergo two years training in AEC at IMA in the corresponding course of non- techni cal permanent commission. While the train ing period of AEC is fixed at one year. The proposition that for the petitioner the train ing period would be two years in AEC since the petitioner was described as non-techni cal would be very difficult to accept when technical or non-technical as the case may be training meant for AEC, is one year. There can not be a different standard for the petitioner who has in AEC in SSC and who was inducted in AEC at IMA through inter view, admittedly without any written test or other examination. The said order does not disclose any provision under which con clusion has been arrived at. The other ground that he cannot be compared with technical graduate is also wholly irrelevant. Inasmuch as the other technical graduates do have additional two years anti-dated seniority from the date of successful com pletion of the training. The said order does not disclose any provision under which con clusion has been arrived at. The other ground that he cannot be compared with technical graduate is also wholly irrelevant. Inasmuch as the other technical graduates do have additional two years anti-dated seniority from the date of successful com pletion of the training. Whereas the petitioner is not claiming such benefit. Therefore, it is not required to compare the petitioner with the technical graduates. Army Instruction No. AI/105/61 itself prescribes period of training of 12 months, which is a type in particular with which the petitioner is concerned. Admittedly, the period of training in AEC at IMA is 12 months and at OTS, Madras, ten months. The entry at OTS being in AEC and at IMA also being in AEC there cannot be any dif ference simply because the petitioner was described as non-technical, basis whereof has not been spelt out either in the counter-affidavit or at the time of hearing. It is very difficult to accept the reasonableness of the order, dated 29-2-1988 (Annexure-3 ). Therefore, in the eyes of law the said order cannot be sustained. 17. On the other hand the order dated 11-7-1989 (Annexure-SAl) does not give any reason. The only expression used for rejecting the petitioners claim was coined as "after perusal of relevant record, "the Government" is satisfied that no injustice has been done to him " (petitioner ). By no stretch of imagination the above phrase can be treated to be a reason. It is very difficult to ascertain as to what passed through to the mind of the authorities, it does not indicate anything to show that he has applied his mind. The expression used can not be brought within the realm of reasons. What is reason is very difficult to define. But it seems reason is something which indicates the process leading to a conclusion on the basis of certain material justifying the decision, and is a manner of expression con veying application of mind and rational process of thinking, though it may be very brief and need not be elaborate and may not be a judgment in that sense. 18. In that view of the matter the orders dated 29-2-1988 (Annexure-3) and the order dated 11-7-1989 (Annexure-SA2) are liable to be quashed and are hereby quashed. Accordingly, a writ of certiorari to issue. 18. In that view of the matter the orders dated 29-2-1988 (Annexure-3) and the order dated 11-7-1989 (Annexure-SA2) are liable to be quashed and are hereby quashed. Accordingly, a writ of certiorari to issue. Since we are of the view that the petitioners seniority is to be fixed in terms of clause (b) of the Army Instruction No. AI-3/s/70 in AEC, after deducting the period of training in SSC at OTS, Madras from the period prescribed for training for the type of permanent commission entered in AEC at IMA the deduction of training period for fixation of seniority would be for a period of two months only and thereby seniority of the petitioner is to be fixed on 29-6-1973. Accordingly a writ of mandamus do issue commanding the respondents to fix the seniority of the petitioner as on 29-6-1973 instead of 29-6-1974. 19. In the result the writ petition suc ceeds and is hereby allowed. There will be, however, no order as to costs. Petition allowed. .