He therefore proposes to construct a new system,[5] analogous to physics (Naturforschung: PsW: 10), to avoid the pitfalls and disprove the theory of faculties (LPs [1850]: 5).[6] The new psychology must, like the natural sciences, assume that all phenomena are governed without exception by a set of laws, which scientists seek out through the establishment of the facts; prudent conclusions; tested and corrected hypotheses (LPs [1850]: 9); and, wherever possible, through the measurement of magnitudes and mathematical calculation (PsW: 10). Similarly, Herbart argues, our mental representations are subject to a system of laws that let us discern the regularities of their interactions (cf. SW V: 195).