Nothing is certain ??? You can't even trust your own eyes !
Thats not a gif or a video (videos are not directly hosted on steemit)
What you see above is an optical illusion.
But there are also auditory, tactile and temporal illusion.
Here is a neat example of an auditory illusions.
The shepard tone is an auditory illusion which seems to rise higher and higher but never really does.
So now that we established that out senses can't be trusted, The practice of radical skepticism seems fitting.
So nothing is know 100% for certain, moving down the scale, 75 % and up for anything you witnessed first hand .
The rest is self explanatory.
Thoughts on the scale, I am looking to develop this further so If you are interested please let me know.
Hope you enjoyed and learned something new, thanks for all the support
Source
https://en.wikipedia.org/wiki/Illusion
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