JPG & loss of quality

I got into a discussion with my FIL (kind of a know-it-all about everything) today about photo size and quality and he told me that every time that you OPEN a JPG it loses image quality. I looked it up in my photo books and it says that so long as you do not save the file after opening it it will not lose any quality. Im going to assume the book is correct as it is written by a professional photographer.

Since I know there are alot of photographers on the message board thought Id ask on here if you open a JPG does it lose quality simply from being opened? What about if you edit it WITHOUT saving will it lose quality then?

The whole reason for this discussion is he said he does not save his photos as high quality because they take up to much room on the hard drive. I said well I dont want to lose the quality of the picture by sizing down so much. He said oh well you can always resize it bigger. And I was like Yea but then the photo looks like crap. So he says yes but you lose quality every time you view the photo. Of course I knew I had read otherwise but could not prove it so I just said ok and let it go.

http://graphicssoft.about.com/od/formatsjpeg/a/jpegmythsfacts.htm

He's wrong.

From the above link:

JPEGs lose quality every time they are opened and/or saved.

False. Simply opening or displaying a JPEG image does not harm the image in any way. Saving a JPEG repeatedly during the same editing session (without ever closing the image) will not accumulate a loss in quality. Copying and renaming a JPEG will not introduce any loss, but some image editors do recompress JPEGs when the Save As command is used. To avoid more loss you should duplicate and rename JPEGs in a file manager rather than using "Save As JPEG" in an editing program.

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If I'm working with a JPG file, I open it, duplicate it and close the original immediately. I never edit the original JPG file, never.

I figured he was because essentially that is exactly what the book says as well.

he has also told me that DVD's and CD's do not corrupt (or do so very rarely) and that hard drives rarely fail LOL

So he lives in a fantasy land where everything is perfect and good. Got it.

yep pretty much!! I have to physically prove something to him when I know Im right but most of the time I just ignore it because with people like that you cannot ever be right. They will still believe whatever it is they believe even with it documented in a book or website KWIM?

A few years ago there was an email floating around saying you needed to delete this file on your computer that had a teddy bear icon next to it cause its supposedly a virus. I told him no its not and he wanted to argue oh yea it is I got my info from this computer builder who told me to delete the file. So I sent the info from three different virus sites and directly from Microsoft and he still did not believe me!! So I said fine delete it.

Leila said:

So he lives in a fantasy land where everything is perfect and good. Got it.

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bwahahahahaha! Leila, I <3 you.