Every Program Has (at Least) Two Purposes:

To Understand A Program, You Must Become Both The Machine And The Program.

A Language That Doesn't Affect The Way You Think About Programming Is Not Worth Knowing.

You Can Measure A Programmer's Perspective By Noting His Attitude On The Continuing Vitality Of Fortran.

You Think You Know When You Learn, Are More Sure When You Can Write, Even More When You Can Teach, But Certain When You Can Program.

Adapting Old Programs To Fit New Machines Usually Means Adapting New Machines To Behave Like Old Ones.