These three engineers signed up for an anatomy class as their cross-disciplinary science requirement. One night they were studying together and started to theorize about God.

The electrical engineer said that God must be an electrical engineer. "After all," he said, "look at the nervous system. It's all electrical."

The mechanical engineer said, "No, God has to be a mechanical engineer. Who else could have designed this kind of skeletal and muscular system?"

The third guy, a civil engineer, said, "You're both wrong. God was a civil engineer."

The other two looked at each other funny and finally asked why.

"Well," said the civ E, "Who else would run the sewer through a recreational zone?"