But the rebellion against systems has another more serious cause, less literary and more philosophical. Sometimes the demand for a system becomes a _systematic prejudice._ This fact merits explanation, because thus stated it may reasonably appear to be paradoxical. However could the demand inherent in a function be changed into a prejudice, or into an obstacle to that function? Stated in these terms, it certainly seems inconceivable. But it becomes clear and admissible, when we remember that philosophical enquiry is both induction and deduction, the thinking of distinction and the thinking of unity in distinction. Neither of the two processes, which are one single thing, should be substituted for or dominate the other. If we think the concept of morality, it should be placed in relation to and deduced from the other forms of the spirit and thus from unity; but it must also be thought in itself. The thinking of the peculiar nature of the moral act cannot remain isolated and atomic, but unity in its turn cannot give the character of the moral act, unless this act be present to the spirit and make itself known for what it is. In the process of research, it is possible to deduce the moral act from the consideration of the other activities of the spirit, without thinking it in itself. But here a _heuristic_ process is adopted, a _hypothesis_ is made, and this hypothesis must afterwards be verified, in order to become effective thought and concept. Now the systematic prejudice consists precisely in thinking the unity without thinking the distinctions, in deduction without induction, in changing the hypothesis into a concept without having seriously verified it. Hence analogical constructions (or falsely analogical, and so metaphysical and fantastic), which take the place of philosophical distinctions, and hence the systematic prejudice, which is a _false idea of system._ Against this rebellion is justified. But the mistake is usually made of discarding the true demand for system through horror of the false, or of denying the utility of the analogical process, which is blameable in the system, but useful in enquiry. [Sidenote: _Sacred and philosophical numbers; meaning of the demand which they express._]