When someone asserts without proof, it means they are making a statement without any evidence to support it. This type of behavior can be frustrating and often leads to misunderstandings or conflict. To avoid this, it's important to use words that accurately convey the lack of evidence in the statement. Some synonyms for "asserts without proof" include alleges, claims, declares, proclaims, and asserts baselessly. By using these words, you can communicate that someone is making a statement without any evidence to back it up, helping to avoid confusion and prevent unnecessary arguments. Remember, it's always better to provide evidence and facts when making a statement to avoid any potential misunderstandings.