It is surely a matter of common observation that a man who knows no one thing intimately has no views worth hearing on things in general. The farmer philosophizes in terms of crops, soils, markets, and implements, the mechanic generalizes his experiences of wood and iron, the seaman reaches similar conclusions by his own special road; and if the scholar keeps pace with these it must be by an equally virile productivity.

Summary

This quote emphasizes the importance of specialized knowledge and expertise. It suggests that individuals who lack deep understanding in any specific field have little valuable insight to offer on broader subjects. It highlights how different professions contribute to different perspectives and conclusions. Farmers possess knowledge related to crops, soils, and markets, mechanics draw insights from their experience with wood and iron, and sailors arrive at their own conclusions through their unique experiences. To be worthy of consideration, scholars must similarly possess productive expertise that keeps pace with these specialized fields.