An old philosophical friend of mine was grown, from experience, very cautious in this particular, and carefully avoided any intimacy with such people. He had, like other philosophers, a thermometer to show him the heat of the weather, and a barometer to mark when it was likely to prove good or bad; but there being no instrument invented to discover, at first sight, this unpleasing disposition in a person, he for that purpose made use of his legs; one of which was remarkably handsome, the other, by some accident, crooked and deformed. If a stranger, at the first interview, regarded his ugly leg more than his handsome one, he doubted him. If he spoke of it, and took no notice of the handsome leg, that was sufficient to determine my philosopher to have no farther acquaintance with him. Everybody has not this two-legged instrument; but every one, with a little attention, may observe signs of that carping, fault-finding disposition, and take the same resolution of avoiding the acquaintance of those infected with it. I therefore advise those critical, querulous, discontented, unhappy people, that, if they wish to be respected and beloved by others and happy in themselves, they should _leave off looking at the ugly leg_. * * * * * ON HUMAN VANITY. Mr. Franklin, Meeting with the following curious little piece the other day, I send it to you to republish, as it is now in very few hands. There is something so elegant in the imagination, conveyed in so delicate a style, and accompanied with a moral so just and elevated, that it must yield great pleasure and instruction to every mind of real taste and virtue. _Cicero_, in the first of his Tusculan questions, finely exposes the vain judgment we are apt to form of human life compared with eternity. In illustrating this argument, he quotes a passage of natural history from Aristotle, concerning a species of insects on the banks of the river Hypanis, that never outlive the day in which they are born. To pursue the thought of this elegant writer, let us suppose one of the most robust of these _Hypanians_, so famed in history, was in a manner coeval with time itself; that he began to exist at break of day, and that, from the uncommon strength of his constitution, he has been able to show himself active in life, through the numberless minutes of ten or twelve hours. Through so long a series of seconds, he must have acquired vast wisdom in his way, from observation and experience.