Some statements concern the conscious states of the animal, what he is to himself as an inner life; others concern his original and acquired ways of response, his behavior, what he is an outside observer

From the lowest animals of which we can affirm intelligence up to man this type of intellect is found.

Psychology helps to measure the probability that an aim is attainable.

The real difference between a man's scientific judgments about himself and the judgment of others about him is he has added sources of knowledge.

The intellectual evolution of the race consists in an increase in the number, delicacy, complexity, permanence and speed of formation of such associations.

Human beings are accustomed to think of intellect as the power of having and controlling ideas and of ability to learn as synonymous with ability to have ideas. But learning by having ideas is really one of the rare and isolated events in nature.

When, instead of merely associating some act with some situation in the animal way, we think the situation out, we have a set of particular feelings of its elements.