Does a regular Christian have more common sense than the world's greatest philosopher?
Yes. God has imparted wisdom to the believer by virtue of being saved, so a regular Christian has more common horse sense than the greatest educated philosopher. Paul drives this home, emphasizing that believers possess a wisdom the world lacks.
Les teaches that in 1 Corinthians 6, Paul addresses believers taking disputes before unbelievers. He reminds them that the saints will one day judge the world and even angels, so they should be able to settle small matters within the local church. Les emphasizes that the world has none of the wisdom God has imparted to every believer. God gives wisdom to the believer simply by virtue of being saved. Therefore, a regular Christian has more common horse sense than the greatest educated philosopher. Paul drives this home and urges believers to use that wisdom.