सुश्रान्तोऽपि वहेद्भारं शीतोष्णं न च श्यति । सन्तुष्टश्चरते नित्यं त्रीणि शिक्षेच्च गर्दभात् ॥

Although an ass is tired, he continues to carry his burden; he is unmindful of cold and heat; and he is always contented; these three things should be learned from the ass.