Is a wise enemy better than a foolish friend

 Once upon a time, a wealthy merchant in a small town had a son. The other day his son's friends came to his house and took his permission to go out with the boy to picnic. They left the town and played at a farm. Suddenly the boy fell and broke his leg. There were two boys among his friends. The first was his enemy, a talented, smart, wise guy. The second one was his close friend who liked the merchant's son extremely, but he was silly. The boys got panic, and they were looking for a solution. The fool guy said:" We should throw him in the well. So, we can go back home, and anybody can't figure out what happened." Most of the boys agreed with him, but the wise guy disagreed and answered:" Maybe it's a good solution for you, but if the boy doesn't return home, his family will think it is my fault because I'm their son's enemy." The wise boy came back to the merchant and explained the events, and they brought a doctor to the field to fix the son's leg

There are some sayings about friendship to fool people in Persian. For instance, we have 

 دوستی با مردم دانا نکوست                           دشمن دانا به از نادان دوست

دشمن دانا بلندت می کند                                  بر زمینت می زند نادان دوست

 which means: A wise enemy better than a foolish friend. A wise enemy will exalt you, but a foolish friend will knock you down. The second and third ones say

چو دانا تو را دشمن جان بود        به از دوست مردی که نادان بود

فردوسی

دشمن دانا که غم جان بود            بهتر از آن دوست که نادان بود

نظامی

The second verse belongs to Ferdowsi and the third one belongs to Nezami. Both have a same meaning: It's better for you if you have an enemy who wants to kill you than a dumb friend

There are some sayings in English too. For example: Whoever walks with the wise becomes wise, but the companion of fools will suffer harm. Or “Nothing is as dangerous as an ignorant friend; a wise enemy is to be preferred.” (Attributed to Jean de La Fontaine)

But how is the situation in the real world? Is a wise enemy better than a foolish friend? The answer is yes. A fool friend wastes your time, money, and energy. He depletes your resources by getting your attention to stupid kinds of stuff, although you can spend them on improving your life. A wise enemy, on the other hand, keep you alerted and wary. You should save your resources to encounter him, which can improve your ability to deal with difficulties. I prefer to have 100 wise enemies instead of one stupid one