Depends...
John in NM
My mom always said to just toss anything you doubted - roughly along the lines of Dick's logic, your health and even just your peace of mind is not worth a few bucks in replacing old food.
On the other hand, I've spent much of my working life at remote sites, and on occasion, cutting the mold off of a block of cheese was preferable to the other options. Cheese is the one thing where I don't even worry about it, though I tend to clean the knife between cuts to prevent mold re-growing the next day. But then I also don't even try to salvage moldy bread - simply not possible compared to something dense like cheese.
Scooping the mold off the top of an opened jar of jam or something similar used to be more commonly done in my grandparent's days. Food was not as cheap then. Most of my motivation is dislike of the taste of moldy food. I don't worry about the health consequences of a tiny amount of mold I missed on some cheese - it just reduces my enjoyment of the food.
The anaerobic bacteria in improperly canned goods would be a much bigger worry to me than a bit of aerobic mold.