How many spaces should there be between a full stop and a new sentence?
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Comments  (Page 3) 
If I were speaking to you, I'd be using subtle breaks between my spoken words to help to convey meaning. When I type, there is no such facility. Therefore, the punctuation marks and the spaces on the typed page take on enormous importance, in order for you to 'hear' my printed words. The double space adds more to this process than the single space. It shows you with utter clarity where one 'bite' of my meaning ends and the next begins. I am not typing this in order for it to 'look professional' or 'look modern'. That would be as absurd as your straw-man dismissal of 'very old books'. Interestingly, you strike me as an individual who values style over substance. The double full stop is necessary (www.it diferentiateswithabsoluteclarityinter-sentencebreaksfrom intra-sentencepunctuation.con). You can now hear - as well as see - what I mean.
I agree. There are countless web pages that 'look professional' and fail to communicate a voice or communicate a stuffy persona.

'Conventions' often block effective communication and 'readibility' is a term often used when someone yearns 'predictibility'. Readibility, yes, but not at the expense of voice.
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