In his book Our Light and Delight: Recollections of Life with the Mother, Amal Kiran alias KD Sethna has devoted a chapter titled The Mother and Sri Aurobindo in the Light of Numerology. In this chapter, Amal Kiran has shown how ‘meaningful numerology’ has served as a light on the lives of both Sri Aurobindo and the Mother. For instance, Sri Aurobindo’s name has twelve letters and Amal Kiran has pointed out how a 12 year-period has served as important milestones in his sadhana post-1914, that is, from the time he met the Mother on the physical plane. Amal Kiran writes about his observation: ‘In 1926 there was the descent of the Overmind into his physical being as well as the Mother’s. Although the Supermind had been already present in the body by 1938 in the sense that it had descended into the embodied complex of mental, vital and subtle-physical beings, it descended in 1938 into the outer physical being for the first time. What could not be done then was to fix it there. In 1950 Sri Aurobindo gave up his body in a strategic self-sacrifice and the Supramental Light was drawn for good and fixed in the physical mind of the Mother, constituting what he had called the Mind of Light.’  Thus we observe that at a regular gap of twelve years Sri Aurobindo attained significant yogic achievements. And let’s not forget that according to the Mother, Sri Aurobindo’s spiritual number was twelve which denoted New Perfection.
But though Amal Kiran has described briefly the effect of numerology on the ‘lives and labours’ of the Mother he has not gone deep into the subject. A probable reason could be that he was ‘indirectly’ warned by the Mother against ‘going too far’  in his numerological calculations. The present article is an extension, rather sequel, to Amal Kiran’s invaluable research.
The Mother attached special significance to numbers. For instance, 4 symbolized Manifestation, 5 represented Power, Six denoted Creation, 7 symbolized Realization and 8 denoted double manifestation and double protection.  There are six letters in the word ‘MOTHER’ which, as we know, denotes Creation. If we consider the Mother’s original name—which was—Blanche Rachel Mirra Alfassa, then we would come across 25 letters, that is, 2 + 5 = 7, thus denoting Realization. But the Mother had dropped one ‘r’ from her name after coming to India  and the new spelling of her name was Mira. Following the revised spelling, the total number of letters in the Mother’s name was 24, that is, 2 + 4 = 6.
Just as a 12 year period marked important milestones in the yogic life of Sri Aurobindo, a 6 year period marked similar landmarks (both worldly and spiritual) in the life of the Mother as well. We shall commence counting these landmarks from 1908, the year her divorce from Henri Morisset (her first husband) took place and she began to live on her own. Six years later in March 1914 she met Sri Aurobindo; in 1920 she returned from Japan to Pondicherry and settled there permanently to collaborate with Sri Aurobindo in the path of integral yoga. It was again six years later in November 1926 that Sri Aurobindo withdrew into seclusion following the descent of the Overmind consciousness in his physical body and the Mother took charge of the newly formed Ashram. Following her recovery after a serious illness between 18 October and 24 November 1931 due to which she had to withdraw from all her activities (the Soup Distribution ceremony ceased forever due to this illness), she began to appear on the balcony at the back of the Ashram main building from 1932; this marked the beginning of the ‘Balcony Darshan’. Six years later, in November 1938, Sri Aurobindo met with an accident and fractured his knee. In 1944 both Sri Aurobindo and the Mother used their spiritual powers to halt and reverse the Japanese invasion of India. In 1950 Sri Aurobindo descended into death and the Mind of Light was transferred to the Mother. In 1956 the manifestation of the Supermind took place. In 1962 the Mother retired to her apartment on the second floor of the Ashram main building never to step outside the building again; the same year witnessed her resurrection in the night of 12-13 April.  And finally 1968 witnessed the birth of Auroville. Thus we see that at a regular interval of six years, important events and significant spiritual landmarks took place in the Mother’s life.
What else could be the ideal conclusion except the following instruction of Amal Kiran that “in relation to the Mother and Sri Aurobindo we should accept large numerological significances without making a fetish of numerology.” 
 Amal Kiran, Our Light and Delight: Recollections of Life with the Mother, pp. 223-224
 Ibid., p. 225
 Mona Sarkar, Sweet Mother: Harmonies of Light, Part II, pp. 59-60
 Information provided to the author by Janine Morisset, the Mother’s granddaughter
 Refer to Mother’s Agenda, 12 June 1962, 7 August 1963, 9 March 1966 and 24 May 1969
 Our Light and Delight, p. 225