167. How does intelligence differ from memory? 168. How does the text describe “lack of intelligence”? 169. How does human intelligence differ from that of animals? § 18. BELIEF It seems, then, that all our knowledge is a mere adaptation to external circumstances, that truth is entirely relative, being only a fitting relation between the subject and his surroundings. But are there no truths whose evidence is inherent in them? Are there no axioms which are immediately evident? Is it not our task to derive all other truths from these axioms by means of logical rules the correctness of which we are obliged to admit? Or, if there are also secondary truths, which we recognize as such only because they suit our experience, are not those immediately evident truths a superior kind, preëminently worthy of the name? For example, the logical, mathematical, and religious truths? Our previous discussion of truth and knowledge is indeed insufficient. We called truth any mental state which is in harmony with objective reality, no matter whether this relation of harmony is itself thought of in the truth or not. But we may use the word _truth_, or _knowledge_, in a subjective sense, meaning by it a complex mental state which _includes the thought of its agreeing_ with objective reality; that is, a state which includes the _belief_ of its objective counterpart. Most people take it for granted that knowledge is mental activity which has its objective counterpart. However, there are very many subjective truths to which an objective reality cannot correspond. Christian, Jewish, pagan, and philosophical martyrs have testified with their blood to their faiths, which in certain respects contradict each other. They must, therefore, have sacrificed their lives partly for something objectively untrue. On the other hand, there are objective truths which are not believed; for instance, theories which are rejected for some time, but later prove to be right. We have seen how objectively correct thought originates. Let us now consider the origin of thought which includes the thought of the existence of its objective counterpart; that is, the origin of belief.