If you were asked, “Does your hand belong to you?” you would naturally say, “Of course.”
But ask neuroscientists the same question and they will turn the question back on you: How do you know it’s your own hand? In fact, how do you know that you have a body? What makes you think you own it? How do you know where your body begins and ends? How do you keep track of its position in space?
Try this little exercise: Imagine there is a straight line running down the middle of your body, dividing it into a left half and a right half. Using your right hand, pat different parts of your body on the right side – cheek, shoulder, hip, thigh, knee, foot. With your finger, trace a line over your right eyebrow and over the right portions of your upper and lower lips.