Oh my goodness, people! It's ART! Stop taking it so literally! Many artists (if not all) will tell you, one of the greatest reasons for creating any art, is to challenge the observers perceptions. To lead the observer to question what they see, think, feel and/or, believe.
You all immediately jump to the notion that 1+1=3 is wrong mathematically but, look at the context of the image and you might see a way that 1+1=3 is correct. What are all of these objects indicative of? How about day to day life? Maybe the day to day life of a couple? Take the thought further. Many couples at some point, through one means or another, bring a third being into the picture. Looked at in this way, 1+1 does in fact equal 3.
How about not even getting that deep? How about just looking at it like this. This collection of stuff when viewed or perceived in one way seems random, without order, perhaps meaningless. But, if the observer only shifts their point of view or the way they perceive the pile, they see a clear message. That message itself being another way of saying that things are not always as they may appear.
Think people! Use your heads for more than a hat rack! Look beyond the obvious. Ask yourself questions like, "is there something more" and then, search for the answer. Who knows, you might just learn a little something. Something about yourself even. And perhaps, just perhaps, grow a little in the process.