principal for her answer, thus showing two mistakes in reading.
Perhaps half of the mistakes that children make in the solution of
problems is due to such careless reading. A certain fifth-year class
in history read a very short paragraph about the three ships that were
secured for Columbus's first voyage, the paragraph ending with the
statement, "On board the three [ships] were exactly ninety men." When
they were asked later how many men accompanied Columbus the common
answer was, "Two hundred and seventy, since there were ninety men on
each ship."

These mistakes are typical of those that are common, even among
adults, as in the reading of examination questions, for instance. I
have more than once asked graduate students in a university to state
the _one principal_ thought obtained from the extended study of an
article on education, and have received a paper with a threefold
answer, (_a_), (_b_), (_c_). Such responses are due to extreme
carelessness in reading the questions asked, as well as to a desire to
be obliging and allow an instructor some freedom of choice. Thus the
meaning of the individual statements that constitute the material out
of which larger truths are derived, must be carefully watched if the
final interpretation of an author's thought is to be accurate.

The tendency toward error is greater still when it comes to finding
the central thought for a portion of text. This was once amusingly
illustrated by a class composed only of the principals and high-school
teachers in a county institute, some seventy-five persons in all. The
text under discussion was the first chapter of Professor James's well-
known book, _Talks to Teachers_. The title of the chapter is
"Psychology and the Teaching Art"; and Professor James, fearing that
teachers might be expecting too much from his field, sets to work to