Total depravity

Total depravity is one the Five Points of Calvinism.
With the fall of Adam and Eve in the Garden of Eden, their descendants spread across the world, taking the first act of evil, the original sin from when they chose to go against God's command, to the ends of the earth. This brokenness has been passed down to all their descendants. As a result, every human being is born with a sinful ethos, incapable of choosing good without divine intervention, and is morally corrupted in all aspects of life. All humans have total depravity from the moment of conception, and can only be brought out of this by God's grace.
The first theologian to explicitly espouse the doctrine of total depravity was Augustine of Hippo in the 5th century. He stated that since the Fall, all humanity is in a self-imposed bondage to sin. All people are inescapably predisposed to evil prior to making any actual choice, and are unable to refrain from sin. In the 13th century, Thomas Aquinas also taught that people are not able to avoid sin after the Fall, and that this entailed a loss of original righteousness or sinlessness, as well as concupiscence or selfish desire.
Following the Protestant Reformation, John Calvin used the term total depravity to mean that, despite the ability of people to outwardly uphold the law, there remained an inward distortion which makes all human actions displeasing to God, whether or not they are outwardly good or bad.
At the Synod of Dort, the doctrine of total depravity was formalised to mean that every part of human nature, mind, will, and emotions, has been corrupted by sin, leaving people completely dependent on God’s grace for salvation. The council emphasized that, while humans are not as evil as they could be, they are entirely incapable of turning to God on their own.