The concept of avidyā or ignorance is central to the Advaita Vedāntic position of Śȧnkara. The post-Śaṅkara Advaitins wrote sub-commentaries on the original texts of Śaṅkara with the intention of strengthening his views. Over the passage of time the views of these sub-commentators of Śaṅkara came to be regarded as representing the doctrine of Advaita particularly with regard to the concept of avidyā. Swami Satchidanandendra Saraswati, a scholar-monk of Holenarsipur, challenged the accepted tradition through the publication of his work Mūlāvidyānirāsaḥ, particularly with regard to the avidyādoctrine. It was his contention that the post-Śaṅkara commentators brought their own innovations particularly on the nature of avidyā. This was the idea of mūlāvidyā or ‘root ignorance’, a positive entity which is the material cause of the phenomenal world. Saraswati argues that such an idea of mūlāvidyā is not to be found in the bhāṣyas (commentaries) of Śaṅkara and is foisted upon Śaṅkara. This paper attempts to show that although Śaṅkara may not have explicitly favoured such a view of mūlāvidyā, his lack of clarity on the nature of avidyā left enough scope for the post-Śaṅkara commentators to take such a position on avidyā.