Finally, it must be remembered that all human happiness consists in part of the ability to bear pain--to suffer. There must be the dash of Stoicism in the wise Epicurean. One must learn to pluck from pain, suffering, and unhappiness the secret drop of honey which lies at its heart, and which consists in the knowledge of the meaning and use of pain and the means whereby it may be transmuted into knowledge and experience, from which later happiness may be distilled. To profit by pain, to transmute suffering into joy, to transform present unhappiness into a future greater happiness--this is the privilege of the philosopher. * * * * * The mental states and activities known as "desire" are a direct development of the feeling and emotional phase of the mind and form the motive power of the will. Desire, in fact, may be said to be composed of feeling on one side and will on the other. But the influence of the intellect or reasoning faculties has a most important part to play in the evolution of feeling into desire, and in the consequent action of the will by the presentation and weighing of conflicting desires. Therefore, the logical place for the consideration of the activities of the intellect is at this point--between emotion and will. Accordingly, we shall leave the subject of feeling and emotion for the present, to be taken up again in connection with the subject of _desire_, after we have considered the intellectual processes of the mind. But, as has been indicated, we shall see the presence and influence of the feelings and emotions even in the activities of the intellect. CHAPTER XX. The Intellect. The class of mental states or processes grouped together under the name of "intellectual processes," forms the second great division of the mental states, the two others being "feeling" and "will," respectively. "Intellect" has been defined as follows: "The part or faculty of the human mind by which it knows, as distinguished from the power to feel and to will; the thinking faculty; the understanding;" also as "that faculty of the human mind by which it receives or comprehends the ideas communicated to it by the senses or the perception, or other means, as distinguished from the power to feel and to will; the power or faculty to perceive objects in their relations; the power to judge and comprehend; also the capacity for higher forms of knowledge, as distinguished from the power to perceive and imagine."