Unshaven and anonymous
Also, I should point out that it is my doctrine of sin and Christ's atoning work that leads me to believe in an historical Adam, not the other way around. The historical Adam is a logical implication, not a logical foundation (at least from my perspective).
That is a little absurd. Of course the doctrines set out in Romans 5 imply the historical reality of Adam: but Paul takes the testimony of the Holy Spirit in Genesis as his foundation. To say that doctrine requires a particular history gives no support to the history unless both are authoritative revelation. And the doctrine is not more inspired than the history.