The heirs of Ed Townsend have filed a lawsuit against Ed Sheeran claiming that Sheeran's hit "Thinking Out Loud" infringes on the Marvin Gaye hit "Let's Get It on." Townsend co-wrote that song with Marvin Gaye.

The Marvin Gaye estate won a huge verdict last year in an infringement suit over Robin Thicke's hit "Blurred Lines." I suspect that may have provided the incentive for this suit.

I have to say, I'm having a tough time seeing the infringement in this case. So here we have Sheeran's song. And here we have Marvin. I'm really wondering if the average listener would be confused by the two songs. They seem pretty distinct to me. And if it takes a music expert, well versed in matters like "melodic, harmonic, and rhythmic compositions," to establish the infringement, doesn't that suggest the listening public isn't confused?

I am not a musician, but I'd be a bit concerned by the notion that stylistic similarities can lead to successful infringement suits. There are only so many notes and so many chords after all. And everyone is inspired by somebody. Maybe I'll write a song about this and call it "Slippery Slope."

And of course, I can't help but make a few random comments on the respective videos. The "Thinking Out Loud" highlights a rule of thumb that I think is immutable -- if you want to look like you know how to dance get a great partner. This is the theory of Dancing with the Stars, and the Thinking Out Loud video nails the point. A mannequin could pull off Sheeran's moves, but who really notices given his partner's skill?

And Marvin Gaye is the world's coolest person. Dead or alive. He will simply never be equaled.