What is the old Adamic nature doing when someone says 'just do it' without thinking about right and wrong?

Les explains that when someone says 'just do it' without worrying about whether it is right or wrong, the old Adamic nature is working and taking sway of a life. Old Adam says, 'forget the law. That's God's side. We're anti-God.' God's Word warns that certain things are harmful and will bring nothing but sorrow and heartache, but Satan and the old nature say, 'but do it. Everybody else is.' Paul says he does what he would not, showing he is rebelling against the good statements of the law.