The most perfect and satisfactory knowledge is that of perception but this is...

The most perfect and satisfactory knowledge is that of perception but this is limited to the absolutely particular, to the individual. The comprehension of the many and the various into *one* representation is possible only through the *concept*, in other words, by omitting the differences; consequently, the concept is a very imperfect way of representing things. The particular, of course, can also be apprehended immediately as a universal, namely when it is raised to the {Platonic} *Idea*; but in this process, which I have analysed in the third book, the intellect passes beyond the limits of individuality and therefore of time; moreover, this is only an exception.
These inner and essential imperfections of the intellect are further increased by a disturbance to some extent external to it but yet inevitable, namely, the influence that the *will* exerts on all its operations, as soon as that will is in any way concerned in their result. Every passion, in fact every inclination or disinclination, tinges the objects of knowledge with its colour. Most common of occurrence is the falsification of knowledge brought about by desire and hope, since they show us the scarcely possible in dazzling colours as probable and well-nigh certain, and render us almost incapable of comprehending what is opposed to it. Fear acts in a similar way; every preconceived opinion, every partiality, and, as I have said, every interest, every emotion, and every predilection of the will act in an analogous manner