Why does the brain skip over repeated “the” words in sentences?

Question

For example, in this sentence by the the time you are done reading you will have already skipped over the double “the”.

In: 134

Answer 1

While you read (or perceive anything really) the brain works to discern meaning and to try to integrate this meaning into the reality it constructs. Since the second “the” doesn’t meaningfully change the substance of what is written, the brain simply discards it. Only when the presence of the second “the” becomes meaningful (i.e. when you specifically look for it, or for typos in general) does it become apparent.