I am not sure how this works, but this is amazingly accurate.

The picture below has 2 identical dolphins in it. It was used at the Mayo Clinic and later at Fletcher Medical Center in Burlington.

Look at both the dolphins jumping out of the water. The dolphins are identical. A closely monitored, scientific study revealed that, in spite of the fact that the dolphins are identical, a person under stress will find many differences between the 2 dolphins.

The more differences a person finds, the more stress that person is experiencing.

Look at the photograph and if you find more than 1 or 2 differences you may need a vacation.