人类理解研究

Section 2 The difference between fiction and belief lies only in a feeling, which is attached to belief, not to fiction, and which does not depend on the will, nor can it be called up at will. It must be stimulated by nature, as all other sensations are; and it must arise whenever the mind is in that particular situation at any particular time. I can say that the so-called belief is a more vivid, active, strong, firm, and stable conception of objects than the conceptions constituted by imagination alone. Nature has established various connections between various particular ideas, and as soon as an idea appears in the mind, it immediately brings in its related ideas by a slow and imperceptible movement, and brings them to our attention. These principles of connection we have classified into three kinds, one is the relation of similarity, the other is the relation of proximity, and the third is the relation of cause and effect. Only these three ties can connect our various ideas and can give birth to a regular string of reflections or inferences that human beings more or less always have. Here we see that there is a predetermined harmony between the paths of nature and the cicada of ideas. Although the forces that control the paths of nature are completely unknown to us, we see that our thoughts and conceptions are proceeding in the same procedure as the previous works of nature. This mutual conformity is established by virtue of the principle of what is called habit, which is necessary to sustain the race and to guide life in all its circumstances and events. If a present impression does not at once stimulate the idea of those objects with which it often coincides, then all our knowledge must be limited to the narrow limits of our memory and senses. In this way, we cannot use the means to achieve the end, nor can we use our natural ability to do good and avoid evil. If people love to discover and think about the final cause, they have here a wealth of material that they can marvel at and envy.