This growth in the number, speed of formation, permanence, delicacy and complexity of associations possible for an animal reaches its acme in the case of man.

All that exists, exists in some amount and can be measured.

On the whole, the psychological work of the last quarter of the nineteenth century emphasized the study of consciousness to the neglect of the total life of intellect and character

Psychology is the science of the intellects, characters and behavior of animals including man.

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

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.

Whatever exists at all exists in some amount. To know it thoroughly involves knowing its quantity as well as its quality.