Thalassophobia is a fear of oceans, seas, lakes, and deep water in general. Humankind has had a tempestuous relation with bodies of water since the dawn of history. On one hand they offer a bounty like no other environment and on the other hand we drown easily. It's been argued that we have semi-aquatic adaptions but that's a real stretch when compared to a seal or a penguin. We belong on the water like we belong in trees. Yes, we can do it, but should we? Thalassophobics know the answer in their guts: No!
Puddles, brooks, or ponds hold no threat. Human hands and feet can find their bottom and human minds encompass their breadth and depth. But what waits below where man can swim in boundless voids of cool and crushing weight? Do monsters free of gravity's squeezing force grow vast on sinking carrion in forms too vile for mortals to guess? Could unlit miles cover plains of mud extending half a world or more in nights a billion years long? What small things we are to brave the fickle surface even for a moment.
According to Google trends thalassophobia exploded into relevance in March of 2015 then dropped to ten percent of that peak and began a slow and lurching climb that would end in an even higher peak in 2023 before dropping to about fifty percent of that summit. I couldn't figure out what caused the earlier spike in two minutes of searching but the later stuff is probably attributable to people figuring out that there was a relatively untapped vein of horror that was cheap to animate. Also, Subnautica is made to inflict this on people.
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