it is easy to see that if we have a wrong generalization, if
our major premise is invalid, all that follows in our chain of reasoning
will be worthless. This fact should render us careful in making
generalizations on too narrow a basis of induction. We may have observed
that certain red-haired people of our acquaintance are quick-tempered,
but we are not justified from this in making the general statement that
all red-haired people are quick-tempered. Not only have we not examined
a sufficient number of cases to warrant such a conclusion, but we have
found in the red hair not even a cause of quick temper, but only an
occasional concomitant.

THE INTERRELATION OF INDUCTION AND DEDUCTION.--Induction and deduction
must go hand in hand in building up our world of knowledge. Induction
gives us the particular facts out of which our system of knowledge is
built, furnishes us with the data out of which general truths are
formed; deduction allows us to start with the generalization furnished
us by induction, and from this vantage ground to organize and
systematize our knowledge and, through the discovery of its relations,
to unify it and make it usable. Deduction starts with a general truth
and asks the question, "What new relations are made necessary among
particular facts by this truth?" Induction starts with particulars, and
asks the question, "To what general truth do these separate facts lead?"
Each method of reasoning needs the other. Deduction must have induction
to furnish the facts for its premises; induction must have deduction to
organize these separate facts into a unified body of knowledge. "He only
sees well who sees the whole in the parts, and the parts in the whole."

7. PROBLEMS IN OBSERVATION AND INTROSPECTION

1. Watch your own thinking for examples of each of the four types
described. Observe a class of children in a recitation or at study and
try to decide which type is being employed by each child. What
proportion of the time supposedly given to study is given over to
_chance_ or idle thinking? To _assimilative_ thinking? To _deliberative_
thinking?

2. Observe children at work in school with the purpose of determining
whether they are being taught to _think_, or only to memorize certain
facts. Do you find that definitions whose meaning is not clear are often
required of children? Which should come first, the definition or the
meaning and application of it?

3. It is of course evident from the relati