I was speaking quite literally about our sense data. If we cannot trust our senses - and even further our experience of making choices and decisions - then all argument must cease. It's been reduced to: It could all be a dream, all an illusion.
Of course existence COULD all be a dream. But if this is taken as a truth statement that we cannot trust our basic experience of reality, then actual productive discussion must stop. We can no longer trust the instruments of our minds or senses and our 'delusions' of reality are equally invalid.
Life isn't a dream or an illusion, but the talk of "free" will is a wrong perception. There is a will but it is not free.