Bay seniors on the lookout for more challenging conversational topics than Don Draper’s character flaws or the validity of gluten free diets, should take a walk this Sunday in McLaren Park. Philosopher Nathaniel Paluga will be leading one of his bi-weekly walk & talks from noon to 3 on the 2.7 mile Philosopher’s Way Trail. His latest book is called “Defectivism: On the Tension of Being.” The topic for this Sunday’s hike will be Truth. Hard to imagine the topic can be wrapped up in 3 hours. Free.