Gene Fuller wrote:
There is no justification for saying that interference causes
superposition or that superposition causes interference or any such
combinations.

That's really good because I didn't say anything like that.
Please don't try to imply that I did.

Superposition can occur with or without interference.

Interference can occur with or without wave cancellation.

If you were to read Born and Wolf you would find that they deal with the
multiple interference problem (antireflective glass) in exactly the same
manner. They never even mention constructive or destructive interference.

I've moved and can't find my Born and Wolf but Hecht certainly
holds constructive/destructive interference in central
position in his classic book. He devotes an entire chapter
to interference.
--
73, Cecil http://www.w5dxp.com