Intellectual Powers.
The power to gain ideas by the five senses is called sensation or perception.
The power to have ideas without the use of the senses is called conception.
Per is the Latin word for by, and con is the word for without. So we have perceptions by the senses, and conceptions without the senses.
Imagination or fancy, is the power to make new combinations of our conceptions.
Memory is the power of recalling past ideas, and of recognizing them as having existed before.
Judgment is the power of comparing ideas, and noticing their relations to each other.
Abstraction is the power of noticing certain parts or certain qualities of things, while other parts or qualities are unnoticed.
Association is the power of recalling past ideas according to certain modes, called laws of association.
The above powers are usually classed together, and called the intellectual powers, or the intellect.
The Susceptibilities, or Feelings.
The powers of feeling various kinds of pleasure and pain, happiness and misery, enjoyment and discomfort, are called the susceptibilities, the emotions and the feelings.
When any thing is found to be the cause of pleasurable feelings, there follows a desire to secure it, and it is called good. When any thing causes pain, a desire follows to avoid it, and it is called evil.
These desires to secure good and avoid evil are called motives (or movers), because they move the mind to action in order to secure the good desired or to escape the evil feared. The objects that cause such desires are also called motives.
For example, gold is called the motive that led a man to murder, and the desire of gold is also called the motive of that act.[4]
Desires are measured as strong or weak by our own consciousness. When we desire two incompatible things and must choose one or the other, before the act of choice we are conscious that one creates a desire which is stronger than the other.
The only mode of deciding which desire is strongest, is by our own consciousness.