§ 3. Feeling-Tone of Ideational Activity itself. Belief. — Ideational activity may assume two forms. On the one hand, it may be directed to the production of some new result in the real world, or to the increase of our knowledge of the real world; on the other hand, it may be a mere play of the imagination. The conditions of pleasure and pain in the two cases are not quite the same, and it will be well to treat them sepa rately. In both cases whatever furthers activity so as to make it more efficient, conduces to pleasure; and whatever obstructs it and makes it inefficient, conduces to pain.
We shall consider first those trains of ideas which are directed towards the production of real results or the increase of knowledge. Two modes of furtherance and obstruction may be distinguished, — the material and the formal.
Material obstacles consist in ideally foreseen circumstances which would actually bar the way to the execution of a plan or to the occurrence of a desired event. As Spinoza says, whatever hinders the body's power of acting hinders the mind's power of thinking; whatever would, in fact, obstruct the execution of a plan, obstructs the formation of the plan, when it is ideally foreseen. If I am planning an excursion and discover that the railway arrangements at a certain place are fatal to its execution, this circumstance arrests the flow of my ideas just as it would arrest their realisation. The belief that a certain event will occur interferes with the ideal train of thought, just as the event itself would interfere with the actual train of occurrences. What has been said of obstacles is equally true of furtherances. The prevision of circumstances which would facilitate the execution of an ideal scheme facilitates its formation. Formal obstacles and furtherances are those which depend on the form of the flow of ideas and not on the ideas themselves. They are due rather to error, ignorance, misapprehension or confusion on our part, than to the actual circumstances of the case. Doubt and contradiction arising at a critical point arrest the flow of ideas, just as the positive prevision of an external obstacle does. If in laying our plans for an excursion we discover, not that the train arrangements at a certain place are unfavourable, but that we have no means of finding out what they are, the flow of mental activity is held in suspense. The belief that there will, and the belief that there will not, be a train fit for our purpose are equally justified and unjustified, so that their conflict blocks the onward progress of thought. Suppose now that one authority, A, says that there will be a train, and another, B, that there will be no train, the state of suspense is intensified. The doubt arising from ignorance passes into the doubt arising from positive contradiction. The statement of the one person furthers and stimulates activity, while the statement of the other suppresses it. If in the long run we come upon evidence which proves that a train runs just at the time we want it, there is a release from tension and an onward bound in the flow of thought which constitutes a highly pleasurable furtherance of activity. Similarly, apart from any previous doubt or contradiction, the mere fact that we find ourselves able to arrange the details of a complex plan so that they fit into each other without hitch or hindrance, is a source of pleasure. Another formal condition of pain is the struggle to find connexion between data which in spite of our efforts continue to appear detached and isolated. This is perhaps best illustrated when we are attempting to follow the train of thought in another person's mind, either by reading or listening. We are looking for a logical connexion between the statements which follow each other; but if the exposition be bad, or the subjectmatter too hard for us, we find incoherence instead of coherence, and the greater our mental effort the more painful it is. A corresponding pleasure is felt when facts which have been previously disjointed and detached in our minds are brought under one point of view, and shown to be exemplifications of the same principle working under different conditions. Here the efficiency of mental activity is increased. "When we discern a common principle among diverse and apparently disconnected particulars, instead of all the attention we can command being taxed in the separate apprehension of these 'disjecta membra,' they become as one, and we seem at once to have at our disposal resources for the command of an enlarged field and the detection of new resemblances."*
* Ward's article "Psychology," Encyclopaedia Britannica, ninth edition, xx., p. 70,