At the bottom of Pritwi Singh's letter Sri Aurobindo wrote an answer:

Nothing needs to be done to bring the ascension — aspiration is sufficient. The object of the ascension is for the lower nature to join the higher consciousness so that (1) the limit or lid between the higher and the lower maybe broken and disappear (2) the consciousness may have free access to higher and higher planes (3) a free way may be made for the descent of the higher Consciousness into the lower planes.

 

PHOTO ID: 00501

SOURCE: Sri Aurobindo and Mother to Prithwi Singh: Correspondence (1933-1967) / Edited by Sujata Nahar and Michel Danino. - First edition. – Faridabad (India): Printed at Thomson Press.- p.100- ISBN 81-85137-4