Central to those considerations are those organized by versions of what is known as the argument from illusion ((6) above).[21] The version of the argument that Austin criticizes can be reconstructed as follows. (i) There are cases of illusion in which we have a sensory experience as of seeing something of some sort with specific features but in which nothing has those specific features. This might be because, although we experience something of the sort in question, the thing we experience la