One old canard is the notion that "total depravity" is (at worst) a uniquely Calvinistic doctrine, or (at best) a uniquely Pauline doctrine, unknown to OT writers, all of whom are supposed to have had an optimistic view of human nature.
One doesn't get very far in Genesis before running into contrary evidence. Of course, there is simply chapter three, which details the death of the first parents, a narrative continued in Adam's fathering of a son in his own (now fallen and depraved) image and likeness in 5:3, with its subsequent, somber refrain of "and he died...and he died... and he died."
But a very clear statement comes in Gen. 6:5 — "The LORD saw that the wickedness of man was great in the earth, and that every intention of the thoughts of his heart was only evil continually." Neither Paul, Calvin nor Owen said anything more comprehensive, extensive or damning.
However, one might attempt the plea, "This is an especially bad generation, not a universal statement. It was why the flood was brought. You can't extend that to everyone."
So what happens next? Noah finds grace in God's eyes (Gen. 6:8), and he and his family alone are preserved alive, while the rest of mankind is destroyed. They, then, are the exceptions. Right?
Wrong. Look at Gen. 8:21 —
And the LORD smelled the soothing aroma; and the LORD said to Himself, "I will never again curse the ground on account of man, for the intent of man's heart is evil from his youth; and I will never again destroy every living thing, as I have done."This is just as universal and unconditional a condemnation as 6:5. But note that it comes (A) after the eradication of the entire evil generation of 6:5, (B) after an act of worship on Noah's part, (C) while the chosen remnant is just beginning its new life in the new world, and (D) before any of them had committed any sin, as far as the narrative is concerned.
(This is developed Biblically at greater length in chaps. 2 and 3 of TWTG.)