There are worse dives in Casablanca, but how do we know that?
We use our senses and discernment, of course. We make Judgments. We discriminate.
The forces trying hard to wreck society disbar us from exercising such faculties of discernment, judgement and discrimination.
All must be 'eeekwall'.
But we naturally know better.
And its is our sense and senses that can lead us to proper (or close enough) conclusions.
And Big Questions lead to big conclusions.
If you want to read all this in greater depth, the Summa Theologica is down in the library next to the Crypt.
On the same shelf is the Capital, though very difficult to read book by Bernard Lonergan.
"Insight: The Study of Human Understanding"
In my very 'Umble Opinion' it would benefit people to read these before blathering about atheism.