I need some help/ideas with my thesis

Since I came up with the following idea for my term paper, I'd appreciate if you could give me your comments and feedback. I would like to argue that humans decide the length of a word based on the frequency of use of that word in every day talk. The more often a word needs to be used, the less syllables it will have when you compare it to words that are not destined for use on practical, every day needs. The reasoning is that, it's more practical and easier to communicate in shorter words to get more work done through the day. Shorter words facilitate faster human interactions. I want to argue that this logic is universal across all languages. Any help, ideas on how to argue this are greatly appreciated. If you are a non-English speaker and your native language has a daily vocabulary which is unusually polysyllabic, please let me know about it, thanks.

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