The bite of the black dog can be worse than its bark. To some, the black dog is man's best friend, a faithful companion in the rear of a pickup truck. To others it is a metaphor for the shadows of depression. Depends, as always, on ones perspective. I was bitten early in life, and though the scars have diminished, the hurt never goes away. Roman lyric poet Horace in 40 BC associated the opaque canine of hopelessness and despair -- a reference resonated in the first century in the writings of Greek orator and philosopher Apollonius of Tyana.
All I know is that I can't sleep at night, haunted by demons of depression that keep me captive in the early hours of the morning.