What Lao Tzu did say is this: Let's make up the "Tao", a.k.a. the way of the universe (or nature) to confuse people and make them foolish. If people are intelligent, they would create all kinds of trouble in society. Remove their "fangs" so they do not hurt one another and can live peacefully together for hundreds and thousands of years. Everyone ought to be dumb and only the noble and governing class ought to be smart. That basically sums it all up. Lao Tzu has been worshiped as a god and his writings as the holy scripture throughout history in the East, but actually, those writings are just gibberish. For example, his well-known signature book starts with "any saying that can be said is not THE saying; any name that can be named is not THE name."

Lao Tzu never said that.

I don't think they had a medical definition for depression back then.

Guess I am a time traveller