A poem theme Be happy

"Nobly does ARISTOTLE observe, that if there were beings who had always lived under ground, in convenient, nay, in magnificent dwellings, adorned with statues and pictures, and everything which belongs to prosperous life—but who had never come above ground,—who had heard, however, by fame and report, of the being and power of the gods,—if at a certain time, the portals of the earth being thrown open, they had been able to emerge from those hidden abodes to the regions inhabited by us; when suddenly they had seen the earth, the seas, and the sky; had perceived the vastness of the clouds and the force of the winds; had contemplated the sun, his magnitude and his beauty, and still more his effectual power, that it is he who makes the day by the diffusion of his light through the whole sky; and when night had darkened the earth, should then behold the whole heavens studded and adorned with stars, and the various lights of the waxing and waning moon, the risings and the settings of all these heavenly bodies, and the courses fixed and immutable in all eternity; when, I say, they should see these things, truly they would believe that there were gods, and these, so great things, are their works."