My Princess Bride reference was very specific.
For the diagram to work as "operations", as you suggest, we would need an order of operations. Moreover, a Venn diagram is not an operational diagram. It is a diagram that demonstrates logical relationships between data sets.
Indeed. But not every set of circles must be a Venn diagram. (In a similar fashion, having a set order of operations might be helpful, but not necessary. After all, the diagram isn't attempting to give people procedural rules, or even procedural outcomes given operating rules.)
My reference above to interpreting things within the confines of our biases, prejudices and frame of reference was not intended to be "oblique" ... or ambiguous.
We all look at things through our inherent frame of reference. It's human nature. If you have little or no frame of reference for Venn diagrams, for instance, you may look at one and see "operations". On the other hand, if you have spent years being educated on Venn diagrams, educating others on their use and utilizing them in your job ... you have a highly defined frame of reference.
And yet, it is still possible to understand things from multiple reference frames. (This is actually pretty common in a lot of different fields.)
Given a particular graphic, one of the useful aspects of the human mind is that we can indeed create multiple meanings from a single image. In this case, that ability allows us to take something that has little logical meaning in one case, a different meaning in another---and for some people, there is a third in which it has
no meaning as their reference frame does not include any of the above information.
Even for people who indeed use Venn diagrams in the manner you describe. After all, mental flexibility isn't limited to people who don't use Venn diagrams.
With a highly defined frame of reference, one should be able to quickly look at something and immediately see what is right or wrong. The risk of a highly defined frame of reference is that new data may be introduced causing that frame of reference to become largely invalid.
The risk of an undefined frame of reference is, of course, quite the opposite.
A risk of a defined frame of reference is that a person may attempt to make all things fit in that reference frame, whether it should be or not.
In common parlance, we of course say "If the only tool you have is a hammer, everything looks like a nail" or some variation. In a similar situation, if a particular person spends a lot of time with Venn diagrams, they might assume that everything that resembles a Venn diagram is therefore a Venn diagram, only a Venn diagram, and nothing else is possible or permitted.
That, of course, is not only a risk, but a logical error.
Apply to your own personal defense and what is "needed" for CCW as you will.
Absolutely.
In this case, we have a great example of how communication is not only based on how clearly a person speaks or presents, but the frame of reference of the person receiving the information. If that person's frame of reference only allows for certain allowed modes, then no matter what mode is meant (particularly if it is multiple modes) then communication will be difficult.
(For example, if I required Venn diagrams to be precise and realistic, the Zombie one you provided is not logically impossible, but at the very least highly incorrect, as there are plenty of things to shoot in the head that aren't zombies----probably in a much higher proportion than there are things that look like zombies that need to be shot in the head. But since my frames of reference include humor, I just find it funny.)