How many donkeys?

Two villagers lived in a small village. The one was rich, the other one poor. The rich villager had a lot of property and livestock, the poor villager didn't have anything.

One day, the rich villager drove 5 donkeys to the market to sell them. He walked, tripped after them and when he got tired got on one of the donkeys.

When he took a little rest, he counted the donkeys which walked ahead of him lop-eared.

- Whew! They are only four! – shouted the rich villager and he jumped afraid on the ground. – The one must've got away, I will come back to find it.

But before that he counted the donkeys again and they were five. Happy he smiled from ear to ear, got on one again and chased the others ahead.

After a while he started counting again.

- They are four again! – He started blinking puzzled.

At the same time the poor villager was coming.

- Neighbour, please, tell me how many donkeys you see ahead of you, because when I count them on the ground, they are five and when I got on the saddle, the one is missing.

The poor neighbour laughed and said:

- The donkeys are six, neighbour, but the one has two legs.