When it comes to giving permission or agreeing to something, "I don't see why not" is a common phrase that expresses a positive response. However, it's always good to have some synonyms up your sleeve to keep things fresh. Alternatives to this phrase include "Sure, go ahead," "Why not?," "Absolutely," "Without a doubt," "Definitely," and "By all means." Using different phrases shows versatility and opens up different avenues of communication. Plus, it's always satisfying to have alternatives ready for repeating the same phrase over and over again. No matter the phrase used, these synonyms convey the same positive response as "I don't see why not".