These puzzles and optical illusions have long fascinated people of all ages for centuries. More than an amusing time killer, they are a wonderful means to exercise the mind and sharpen the thinking process. These puzzles and optical illusions have long fascinated people of all ages for centuries. More than an amusing time killer, they are a wonderful means to exercise the mind and sharpen the thinking process. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle