I’ve been listening to some of the podcasts on Indian Philosophy put out by Peter Adamson and Jonardon Ganeri on history of philosophy It’s good that it is being done but I have to say I found the talk on Advaita Vedanta
to be coarse grained for the undergraduate level at which they aim. What Shankara said was that what we take to be reality is like an illusion not that it was an illusion through and through. In fact the import of what he said is that conventional reality is like a mistake or a confusion. The rope/snake is an analogy with a strictly focussed point namely that an attribute of a real entity i.e. the coiledness of a rope becomes a snake in the mind of a perceiver in poor visual conditions. It is this transfer of attribute that connects to the philosophical concept of superimposition. Adhyasa (superimposition) is linked to Upadhi (limiting adjunct) and to Vritti (mental modification).
This is much more philosophically interesting than to say ‘conventional reality is an illusion’ and it could serve as an introduction to Shankara’s theory of analogy and his ideas on the continuous development of insight in the student. That of course is getting a little deep and far from the shore.