King Solomon Was Able To Understand The Speech Of The Animals And The Birds

Some say that King Solomon truly knew who was the real mother as soon as he saw the two women. This was the nature of the special divine wisdom that God gave him.

As King Solomon was able to understand the speech of the animals and the birds, so he could see the truth in someone's face. His knowledge was of Divine origin. It was infallible.

According to the Abarbanel and Metzudas David, King Solomon studied the countenance of each woman as they presented their claims and counter-claims, and by means of his penetrating and heavenly wisdom, understood which of the two women was telling the truth.

Still, to prove this to the people, he had to demonstrate it in a way that everyone would acknowledge. 

Perhaps that is why he pretended not to know who said what, and repeated their arguments in reverse order, by repeating Woman #2's argument first, and Woman #1's argument second.

HealingMandala

He even pretended to apply the well-known law of dividing disputed property. If two people come to court holding on to the ends of a piece of clothing, and each claims it to be his, the court divides it and gives each one half. 

King Solomon seemed to pretend to be ignorant of the many complicated details of this law, and to think that it applied to babies as well, which would have been ridiculously simpleminded. 

No judge would ever make such a foolish mistake. Yet, he succeeded in convincing the two women that he was serious.

Nonetheless, he was careful not to let the trick go too far. He specifically commanded his servants to bring the sword to him, not to give it to one of the guards. They too, were no doubt fooled and he did not want them to divide the baby before he had a chance to stop them. 

In fact, the King's ministers said "Woe to you Oh Land, whose king is but a boy!" They thought "what has God done to us to give us such a king? How long will we have to suffer with such foolish judgments?" 

But afterwards, when they saw the women's reactions they knew that he had recently received Divine inspiration and rejoiced saying "Happy are you, oh Land, whose king is a free man!" - i.e., one who studies Torah (Koheles - Ecclesiastes 10:16-17).

https://www.jlaw.com/Commentary/solomon.html