I try to see both sides of an argument, but it is hard to justify this policy. It seems inconsistent with the stated objectives of Republican leaders.

The tax bill, we are told, aims to promote economic growth by creating an environment more favorable to investment. That is the main argument for the cut in the corporate tax rate to 21 percent from 35 percent.

But the investment that leads to growth is not just in plant and equipment. It also includes human capital, which means educating our labor force. And it includes the knowledge that flows from basic research. The United States is an economic superpower in part because we have the best university system in the world. The tax bill undermines that.

Republican leaders say that they want to help the middle class. They claim that over time, as corporate tax cuts encourage investment and increase productivity, the benefits will accrue not only to wealthy shareholders but also to workers in the form of higher wages. I believe that, but I also believe that for many people, the surest route to higher wages is increased skills.

My life is a case in point. Neither of my parents were college graduates. But they always stressed the importance of education. Today I am more economically secure than they were throughout their lives because of the skills I acquired in school.