I concede that the quote about the distinction regarding E type lenses was confusing. The point is, and always has been, that an AF-D lens will not autofocus on the old D40 body. Am I right or wrong? That's all I've been trying to say from the start. The "D" in the lenses you referenced in your first post refers to the transmission of distance information from camera to lens (and I think we agree about that as well). Where you go wrong is in referring to these lenses as "D-type" lenses. I am talking about the type of lenses that require a screw drive to auto focus; for example, the AF NIKKOR 50mm f/1.4D and the AF NIKKOR 85mm f/1.4D IF, that I mentioned in my original post. These lenses will not autofocus on the old D40 body. Am I right or wrong?

I am very surprised at your lack of knowledge of AF-S and AF-I "D" lenses Alan. Looks like its time for a refresher course in Nikon lenses for you as well. Just look up any of the AF-S "D" lenses I posted already and you will see clearly that there are MANY Nikon D lenses with AF-S motors in them and ALL will work of the entry level Nikons just fine. "D" does NOT preclude AF from working on those bodies unless AND ONLY IF the lens specifically says AF D! If the lens shows an "S" or an "I" after the AF it will still autofocus on those entry level bodies even though it is clearly marked as a D lens.

No, they aren't D-mount, they are D-type. All Nikon SLR lenses are F-mount, throughout all the various iterations. I thought that was made clear early on . . . The same link you provided clearly references "AF-D" lenses, which is what we are both talking about. The link you are referring to also clearly indicated that the Df camera is unique in that it can use all the different types of lenses, which is NOT true for every other Nikon camera. The page you provided makes that clear -- perhaps you need to pay more attention to details, which is what this whole foolish discussion is about.

The only point I've been trying to make is that the D-type lenses will not auto focus on all Nikon cameras, because they lack an internal focusing motor and rely on a screw drive in the camera body. If the camera body doesn't have that, and the ones I've mentioned previously don't, then those lenses won't be able to auto focus with those bodies. I challenge anyone to find any authority that says otherwise. In fact, here is Nikon's own chart from the same site you provided that says the same thing:

https://www.nikonusa.com/Images/Learn-Explore/Photography-Techniques/2011/Which-Nikkor-is-Right-for-You/Media/NIKKOR-lens-compatibility-chart.pdf

The AF lenses listed are the same ones I'm talking about. The chart lists those camera models which have "Limited Compatibility† Can only be used as a manual focus lens. No AF."

As for my credentials and why I don't believe MT Shooter (and it's only in regard to this one simple issue) -- because I've personally owned the exact cameras and lenses that I'm talking about, as a working pro for the last 15 years. I don't claim to be an expert from reading Rockwell's site (in fact, I have't looked at his site for years before today) and I also provided three other more authoritative sources; did you bother to read those? Otherwise, it seems you are quick to criticize someone who has the facts (but who you don't know) simply in favor of someone you feel you do know, but who doesn't have the correct facts.

off of your own link you just sent the D40/D40X has ai Limited af Compatibility‡ Limited afs Compatibility† Full Compatibility af-p Not Compatible e type Not Compatible, soooo yep looks like they are compatible though limited I buy only used lenses and have a few af-d type they work for me on my D7100 and D800, side note because I shoot mainly landscape I manual focus about 70 percent of the time it really is not a hindrance in any way that I can tell. I did pay attention and usually do not entered this sort of debate but you are trying to put down MT's advice even though he gave correct information.

off of your own link you just sent the D40/D40X has ai Limited af Compatibility‡ Limited afs Compatibility† Full Compatibility af-p Not Compatible e type Not Compatible, soooo yep looks like they are compatible though limited I buy only used lenses and have a few af-d type they work for me on my D7100 and D800, side note because I shoot mainly landscape I manual focus about 70 percent of the time it really is not a hindrance in any way that I can tell. I did pay attention and usually do not entered this sort of debate but you are trying to put down MT's advice even though he gave correct information.

Okay, I give up. You say yourself that you own AF-D lenses, but they work fine with your D800 and D7100. OF COURSE THEY DO! AF-D lenses are fully compatible with both cameras. Try to autofocus one of your AF-D lenses on a D40 -- which was all I ever tried to say -- and let me know how it works for you. This site is clearly the "cult of MT Shooter", and no one is really smart enough to pay attention to what is being said. I have better things to do with my time. I'm going to stick to Nikonians and NikonCafe in the future, where real photographers seem to have no problem understanding basic concepts.

Absolutely incorrect!
"D" has nothing to do with the focus drive, it only designates that the lens has a focus confirmation chip in it that transmits focus data to the cameras PCB.
What determines if a lens will AF on the entry level Nikon bodies you note is the focus drive system of the lens. "AF" designated lenses have the older mechanical screw drive focus motors and will NOT AF on those entry level bodies.
AF-I, AF-S, & AF-P designated lenses have electronic focus motors inside the lens and wil auto focus on any current series Nikon DSLR.
There are several Nikon lenses that carry BOTH the AF-I or AF-S AND "D" designations and will AF on those entry level lenses. I personally own 3 of them. The AF-S 17-35MM F2.8D, AF-S 28-70MM F2.8D, & AF-I 400MM F2.8D.
ALL Nikon SLR & DSLR lenses are made wth the Nikon "F" mount except the very short lived Pronea series cameras.