Let's say I invent a really bad idea. (Left-handed people should be executed by electric chair.)
Then let's say I symbolize that idea with a catch phrase or a logo. (A red hand.)
Now let's say there are an infinite number of people in the world. If I tell ten people that the hand-lightning symbol is the "cool" thing to display on a website, social media post, tshirt, or whatever, and two people agree to post it, then I have two people displaying my symbol, and unknowingly supporting a mass murder proposal.
The next cycle, those two people show the symbol to ten more people each (a total of twenty), and eight of each group ignore it (not out of morality but just out of disinterest), so the remaining two out of each group repeats the symbol. This means four new people have posted the hateful symbol without considering its implications. However, by now, the first two people have learned the symbol's meaning, and have removed it, replacing it with a counter-symbol. (A green hand.)
The next cycle, the four displaying the red hand have seen the green hand and adopted it, but by now have also passed the red hand symbol onto eight more people. This means that now, not counting myself, there are eight red hand symbols and six green hand symbols.
This pattern can repeat itself indefinitely, with the next cycle showing sixteen reds and fourteen greens, and the cycle after that showing thirty-two reds and thirty greens. The pattern will move increasingly closer to a half red and half green, but the reds will always slightly outnumber the greens, because the "bad" symbol is always one generation ahead of the correction.
Now let's say that I want to justify my position by popular opinion. While the red-hand-displayers do not understand the meaning, and while the larger public have either not yet encountered either symbol or have seen one or both and taken no interest, there is no display symbol for indifference or for understanding, so I can extrapolate the opinions of the general public by the symbols on display. If I see more red hands than green hands, I can make the assumption that more people side with the mass execution position than oppose it. Despite the fact that each person displays the red hand for only one cycle, and the supporters of the green hand are growing in number each day, the raw numbers show that red hands consistently outnumber green hands. This validates and strengthens my original position, no matter how many people strongly oppose it.
What's more, the greens, upon seeing the raw numbers are unlikely to dispute it, believing the reds to be posting in earnest. Why? Because people generally like to feel smarter and more moral than those around them, so it's easy for them to accept the idea that 100% of the "others" are in favor of a bad idea.
Of course, in the real world, there are not an infinite number of people, so the common wisdom would be that the pattern would reach a limit at some point, where no more reds can be added. However, due to the fact that the expanse of ideas turns back upon itself several times, the growing will slow over time, and the expansion of the green posts will not necessarily reach all of the red posts. This is why multi-level marketing schemes fail before they reach the entire population, but never die out completely, because there are always a supply of people who may yet be potentially taken in by them. The population may not be literally infinite, but it is functionally infinite.
Consequently, anyone who posts a bad idea reduced to a simple logo or catch phrase (such as "America first" or "All lives matter") the result is that the OP always gets to experience the appearance of mass public support just over half the population, without necessarily having the real support of nearly as many people, or anyone at all.
