I think readability is helped a lot by the low entropy of English words and sentences, i.e. if you can’t make out one letter, you’ll probably get it anyway from the context.

It’s not so readable if you test it with random strings.

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HarHarVeryFunny 3 days ago | parent [-]

I think it's partly because we recognize letters, and whole words, by glyph shape more than specific identity. Obviously a 2x2 grid can only depict 16 different patterns, but we're trying to recognize whole words, not arbitrary letter sequences, and the sequence of shapes (hence letter possibilities) is evidentially enough, a bit like reading crappy handwriting.

It's interesting how we can do this with this 2x2 font immediately without any training, but I suppose reading in general has provided enough training, and ability to read this 2x2 font just provides some insight as to how word perception works.

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tremon 3 days ago | parent | next [-]

Most letters are 2x3 px, the letter m is even 2x5. And I wouldn't say that I could comfortably read this, it was closer to deciphering than reading.

	▲	HarHarVeryFunny 3 days ago \| parent [-]
		True, but it's interesting that we can quickly decipher/read it at all. It seems to be a typical case of human perception where top-down prediction (maybe of visual word forms?) meets bottom-up sensory input, and we've gained enough experience of this (reading different fonts, handwriting, various lighting, etc) that this particular type of impoverished input doesn't pose much challenge.

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NBJack 3 days ago | parent | prev [-]

I believe it's in part because of our experience reading things at angles. In this case, it looks to me like letters tilted backwards on a table, and I'm peering at them just above their horizon. Legible, but not comfortable.