I take it that you’re infralapsarian?
I'm not as certain as the typical Calvinist. For humans with our limited abilities and knowledge to claim absolute certainty in any area goes against all the evidence we have, not to mention basic logic, and is indeed a form of arrogance as has been stated by others on this thread.
Even if one limits one arguments in favor of a particular theology to the Bible, one has to admit that there are numerous conflicting interpretations of the text. To claim that one's particular interpretation is the correct one is the height of arrogance. To claim that one's reading of the Bible is not in fact an interpretation, but is the only clear straight reading of the text, is borderline delusional.
Currently I'm leaning to Molinism...