This world is not flat, it is round. It has people of all types... not just one type, flat.
One of these types is known as 'Dog-in-the-manger types'. They will neither do any good work, nor will allow anyone else to do it. Aesop, in one of his fables, made these fellows very popular, very familiar. This was that fable:
Long time ago, in one of the villages, there lived a farmer. He had a couple of cows and a dog. One day, the cows had been out and, back home, the dog was hungry. He went around everywhere looking for food but in vain. Finally, he landed up at the stable and, found there some fresh hay in the manger. He tried to eat it, but he couldn't. "How unfair can be our Master," he cribbed,” So much for the cows, and nothing for me." Then, he slept in the manger, right over the hay, and declared, "I will not allow those cows to eat it, either."
In the evening, the cows returned to the stable, hungry. But, when they went near the manger, they saw the dog sleeping right over the hay. They pleaded, "Brother, we are hungry. That is our food and you are sleeping over it. Please vacate this place so that we can have our dinner."
The dog ignored the plea from the cows, and refused to vacate.
"Please, our brother," the cows cried, "Look, you can sleep any where else; but let us have our food."
"No way," the dog snarled at the cows, "You go and find your food any where else... and let me take my rest here."
"Try to understand our brother," the cows begged, "You very well know, it is night time, and we are hungry. You cannot eat the hay over which you are resting... but, that is our dinner. If you do not move, we will go hungry."
"That is your problem, not mine," the dog sniped. "Now, will you leave me alone, or else..."
Just then, there appeared the Master. When he saw the dog in the manger, with all his arrogance, bullying the hapless cows, he immediately picked a long stick and sent some nasty blows on the dog's boated head.
Yes, the world is round, and not flat. It has all types. It has these 'dogs' - sorry for that - who will neither eat what is there in the manger, nor will allow others, the 'cows', to eat it. Instead, they will sleep in the manger - right over the hay - and declare, "Let us see, how they will eat it."
For these 'dogs', the 'cows' cannot convince, leave alone 'teach'. Only the 'Master's stick' can!