Subliminal messages provide another interesting scenario. Unlike the “unknown knowns” the next scenario can relate to all humanity. In the well-known Cocoa Cola experiment, which some critics consider a publicity hoax, a private market researcher secretly flashed a few words suggesting people eat popcorn and drink coca-cola in a movie theatre. A higher percentage of people simply followed the instructions increasing the sales of popcorn and coca cola at the theatre. The unknown part here is the subliminal message which flashed on the screen for a small amount of time long enough to have a subsequent effect but too short a time to be cognisant of it. Even if someone tells us what really took place it is less likely for a sceptic in the audience to accept the subliminal message as the reason for the choice. The reason according to them would be something in the vein of what they always do at the movies. Thus, the reason why he or she bought popcorn and coca cola would remain unknown. This is an example of an unknowable known. In my previous article on Medium, “Does God exist? Doesn’t matter” published on 12 January 2023, I discussed this category of knowledge in relation to Blaise Pascal’s arguments on the existence of God. Pascal used infinity as a discussion point.
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