Words from
perennial
    lasting or existing for a long or apparently infinite time; enduring or continually recurring.
    
    Source: Zen and the Art of Motorcycle Maintenance - Robert M. Pirsig
    
    rebuke
    express sharp disapproval or criticism of (someone) because of their behavior or actions.
    
    Source: Zen and the Art of Motorcycle Maintenance - Robert M. Pirsig
    
    oblique
    not explicit or direct when addressing a point.
    
    Source: Zen and the Art of Motorcycle Maintenance - Robert M. Pirsig