To use or not to use symmetry in photography. In photography, symmetry refers an image that has a sense of balance and proportion. This creates a peaceful feeling. In this image, the dog himself is very symmetrical, including his coloring. The background also is symmetrical in color and balance of color.
Or you can create harmony by balancing color, lines across an image. In this image the greenery in the foreground balances with the green in the background. The puppy is perfectly centered and symmetrical in his own right and the scalloped trim is balanced on either side of him.
There could be something said for a little about asymmetry however. In this photo, the dogs head and ears are asymmetrical, however his tail breaks the balance by flying out on the right side. This creates a little bit more interest and somehow the tail balances well with his winter coat that is slightly askew on the left side.
Whether you like symmetric images or asymmetrical images, there is no denying that the subjects are all adorable.