How does shakes sphere introduce the idea of opposites being the same

he says things to make it sound as if one thing is going on but what you think is going on is actually the opposite. he gets your mind wrapped into romeo is going to kill himself when he gets banished but he stays and plans on coming back to see juliet but before he comes back his servant tells him she is dead so he goes to juliets burial chamber and drinks a poison but little does he know she is not dead. so shakespeare makes it look like juliet is dead but the opposite of what he said is the truth