I've always thought that the use of the preposition 'to' with the verb 'convince' is correct. But I recently learned from a reliable source that 'to' shouldn't be used with 'convince' but rather with 'persuade'. So instead of saying for instance 'I should try to convince him to work harder', I'd rather say 'I should try to convince him of his ability to work harder' or 'I should try to convince him that he can work harder' or 'I should persuade him to work harder.'
Honestly, I'm still perplexed. Could anyone shed some light?
Best Answer
Short answer: they're both fine, and you clearly already understand when to use which.
Use of with a noun phrase, to with a predicate, and that for a clause. You gave very good examples of all three in your question. The original reason the to usage was frowned upon is that convince was supposedly only for thoughts and ideas; if something someone said resulted in you actually doing something, then you were persuaded rather than convinced. This rule is rather old. Here's what Merriam-Webster's Dictionary of English Usage has to say:
You can read the rest of the entry on page 297 on Google Books. They also give attested usages from the New York Times, etc.
Eduardo may have a point about the British/American thing. Just a quick search of the BYU-BNC British National Corpus and the Corpus of Contemporary American English, which contain millions of words from published material gave this for the BNC:
and this for the COCA:
Keep in mind that each of these usages differs also in meaning, so be careful what conclusions you draw from these numbers.
You may also be interested in the Google Ngram Viewer.