The phrase "by very fact" is commonly used to emphasize the truth or validity of a statement. However, sometimes it can sound repetitive or monotonous when overused. Therefore, it is essential to have a range of synonyms to vary your writing style. Some of the other phrases that could be used instead of "by very fact" include "undeniably," "undeniable," "inherently," "naturally," "unquestionably," "undeniably true," etc. Using synonyms appropriately not only adds diversity to your writing but also shows a mastery of language and how different words can convey similar meanings.