When swiss cheese turns blue?!

When swiss cheese turns blue?

If you have a wheel of swiss cheese, and it grows moss and starts turning blue, it starts smelling funky; arguably it has gone bad; my question is, will it make you sick? What is the difference between this fungus and the one in Roquefort for instance? We had a 'blind' taste and my brother thought it was funny to give us some of that. . . We need to settle this, Help!

9 minutes ago
I'm ashamed to say it wasn't totally terrible, bad structure, and unbalanced, but waxy and soft, spread over black bread it wasn't that bad. We didn't particularly liked it but we just thought it was low quality.

Well, you probably won't die if that is what was bothering you, but aside from being tasteless your brother isn't all that crazy, after all Roquefort got it's start as moldy cheese. If the cheese in fact turned blue or greenish it probably was inoculated with Penicillium roqueforti or Penicillium glaucum which CAN produce toxins under certain conditions, being that your cheese probably wasn't in a controlled environment I wouldn't try it any more. By the way, how was it?