Judging By This New York Times Story, Steve Mnuchin Is a Liar -- Slate

 Even before Republicans had written a bill, Treasury Secretary Steve Mnuchin insisted that their tax cuts would more than cover their own cost with economic growth. "Not only will this tax plan pay for itself, but it will pay down debt," Mnuchin said in September. Despite this being comically implausible, Mnuchin promised that a crack team of analysts at his department was already looking at the economic effects of various proposals. ....
https://slate.com/business/2017/11/steve-mnuchin-has-been-lying-about-the-tax-plan.html