The woman thought to herself: If he is asking for 10 lira per liter, I
should be able to bargain him down to 8. So she told the milkman, "You
are asking for 10 lira, but another milkman comes by selling his milk
for 8 lira."
The milkman said, "Today, buy the milk for 10 lira, and tomorrow I will
sell to you for 8." The woman agreed.
By the next day when the milkman arrived, she was already having second
thoughts: The milkman accepted the price of 8 lira quite readily; that
means I could have gotten the milk for even less. So she told the
milkman, "You are asking for 8 lira, but another milkman has come by
selling his milk for 6 lira."
The milkman said, "Today, buy the milk for 8 lira, and tomorrow I will
sell to you for 6." The woman agreed.
The next day, when the milkman arrived, he found her still unsatisfied.
She said: "You are asking for 6 lira, but I have found yet another
milkman who can sell to me for 4 lira."
The milkman answered, "Today, buy the milk for 6 lira, and tomorrow I
will sell to you for 4. But I must warn you that at 4 lira per liter it
becomes very difficult to keep the milk white."