It is a normal part of the writing process to change your mind about your ideas. You can change your mind about your argument like you can change your mind about one minor aspect of it. In any case, you are likely to change your mind about one or more ideas because the writing process is a thinking process. You should not be afraid of having to change your conclusions. Although it may involve some rewriting, changing your mind makes you stronger and more articulate. Writing has a way of exposing your logical gaps, blind spots, and biases. Embrace it.
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