There seems to be a temptation lately to label anyone who even dares mention supply-side economics, without immediately deeming it the silliest idea born to a napkin, an economic heretic. That's unfortunate. True, with the exception of very high marginal tax rates, a tax cut will generally not pay for itself. But there exists ample empirical evidence that cutting income taxes does increase growth. Thus, the long-run impact of a permanent tax cut is still up for debate. The effect of lower-income tax rates on labour supply is mixed. But it does seem, at the very least, lower tax rates decrease the amount of tax evasion. Writing off supply-side economics as a blatant fallacy is as much of a 1990s relic as wearing a goatee.