Since writing is a subset of symbols, much of the advice given about understanding language applies here. You must find out what the user of the symbol means by it and sometimes it varies widely. Take for example the modern peace sign. An upside down forked symbol in a circle. What does it mean? Well, the original creator of it took the flag semaphore symbols for N (a man holding each arm down at a 45 on each side) and D (a man holding one arm straight down and the other straight up) for Nuclear Disarmament. It didn't take hold until they added a circle around it.
Now, what does the modern peace symbol mean? Here is a partial list: identifying sign for the Nuclear Disarmament group in the UK, the footprint of the American Chicken, a dove's print in a circle, a broken cross, the sign of the Antichrist, an rune of life inverted to symbolize death, Nero's cross, a symbol of the devil and other variations. Speaking of people incapable of discernment:
PEACE SYMBOL - Also known as the Cross of Nero. Many people are not aware of the origins of this symbol or how it became to symbolize peace. This is the cross of Nero, a broken and inverted cross, enclosed in a circle which represents Nero's vision. Nero believed that there would be world peace without Christianity, thousands of Christians were martyred under the rule of Nero. This is what the "peace symbol" represents regardless of what it means to you.
Their way or the highway, despite well documented historical evidence that it was created by a man who wanted a simple symbol for the Campaign for Nuclear Disarmament. You see that often in marginal groups, they force a definition linking similar symbols and assert their authority, but if you actually check, the symbols in question were created years or decades apart with no connection between the two sources. Somehow, someway, somewhere, there simply MUST have been some communication though, because it fits the group's agenda.
When I see an old kungfu movie filmed at an old temple in China, do all the swastikas about mean that the worshipers there were proto-Nazis, they were just using a good luck symbol in their decorative work or were the producers of the film neoNazis?
Often people and groups use such rigid definitions to force a conclusion in line with their presuppositions. Research the symbology of the snake or serpent in Scripture. Is it Satanic? Or is it wisdom? What about the Son of Man being lifted up?
How about the circle? Is it a female symbol? Symbol of the One God? Eternity?
Is the triangle the Trinity? A doorway for demons?
How about the famous fish symbol? A symbol of Christ? Or a female symbol?
Shall we go to the cross itself? Did it have a Christian use before Constantine saw the Chi Ro vision? Did it have any other symbolic uses prior to Christ? I actually find this one sadly amusing. I read a post by a lady railing against a group using what she described as “Babylonian sun symbols” as some kind of proof about something. In her signature was a cross, the earliest use of which was in Babylonian sun worship. It also was a fertility symbol from the pagan beliefs about the sky 'fertilizing' the earth.
Now, some people do define some of these symbols in a negative fashion, I'm not saying they don't, but until you know what they mean to the one using them, you cannot call it that.