(CNN) On Saturday morning, before most people were awake, President Donald Trump was tweeting about how very, incredibly, stupendously smart he is.

"Throughout my life, my two greatest assets have been mental stability and being, like, really smart," tweeted Trump . "Crooked Hillary Clinton also played these cards very hard and, as everyone knows, went down in flames. I went from VERY successful businessman, to top T.V. Star to President of the United States (on my first try). I think that would qualify as not smart, but genius....and a very stable genius at that!"

His tweets came in reaction to the less-than-flattering picture painted of him in Michael Wolff's new book, "Fire and Fury." The portrait of Trump is of someone viewed as a child by those who work for him and who appears to act that way as well -- impetuous, bullying and unaware of what he doesn't know. Wolff himself has said that those around Trump believe he is deteriorating mentally.

To which Trump responded with a flurry of tweets insisting he is the world's greatest super-genius.

Is he? Who knows? Trump talks about how smart he is all the time. I haven't seen his IQ test, and, of course, being very smart is not a prerequisite for being president.

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