I think a break from perspective theory is welcomed so here it is, but we will come back in a few days with one last perspective theory hint.
Today’s visual optical illusion represents mostly an ambiguous image that you have to interpret in your own way and through your own needs or desires.
What to see?
Just by asking this thing it feels redundant because it is quite easy to realize that the picture represents the silhouette of a beautiful woman. I think that the picture is drawn, not taken to an actual person.
What you have to analyze in this picture is to see if the girl is facing towards you or facing the other way around, away from you. For you to find out you have to analyze her entire body position starting from head to toes.
How does it work?
There is not special trick in this image and the only reason why we call it illusion is because we have a doubt about the way the silhouette is facing. In general we don’t even ask ourselves this kind of questions because we “know” for sure. But this knowing is based on what our brain wants to perceive.
For instance I could say that the girl is facing away and you can say she’s facing towards you, but none of us can say a real reason, although if we analyze the margins of the picture we can tell that in this particular one she is facing towards us because of the way her feet are positioned.