let us not forget that sometimes illusions and reality overlap. All people share unique characteristics, not so visible to the naked eye, making them unique... they're past and DNA for instance.
Some illusions have real and dire consequences... one lives in an illusion (we are actually "born" in its amidst - in that huge social awe and distortion)
Illusions are ideals and thoughts which are taken as certain... They are vast masses of little things!