The way ordinary encyclopedia selects information is more accidental than principled because it compiles a set of viewpoint and in doing so invariably exclude other views. It gathers all the information relevant to a general topic and just offers the convenience of the information being there when the topic is searched. But it makes no effort to negate or critically question the particular facts to construct a general picture about the whole topic. A medical encyclopedia for instance tells you all about the different types of medical diseases, symptoms, treatments and prognosis, but it does not go into the deeper topic of why certain human behaviour result in health issues. Psychoanalysis for instance goes into these deeper questions and therefore it can be an ontological science.
Normal encyclopedias stay away from the reason why things happen, they only offer the description of what happens. For example a doctor does not ask the patient why they smoke, he just simply reviews the case of disorder in front of him and hopes to do the necessary operations to alleviate it, like a mechanic fixes a broken car, he does not ask why it was in an accident because that is not relevant to the task at hand. In philosophy all facts are relevant because this forms part of what logic means to be a comprehension, or in other words, comprehensive.
A philosophical encyclopedia operates on the prejudice that there is right and wrong knowledge. Now as to whether there is true or false knowledge is a subject matter that becomes clearer throughout the duration of the inquiry, but it is nevertheless an assumption adopted in the onset of an ontological study in order to collect information. To differentiate between true or false knowledge is by no means an easy task, but one thing is for sure in a system where all possibilities must be ascertained, is that the first wrong move is to assume there are no wrong moves. These are truths in the first set of assumptions the philosopher must initially adapt before selecting information he or she judges to be true. Hegel says;
“In the form of an Encyclopaedia, the science has no room for a detailed exposition of particulars, and must be limited to setting forth the commencement of the special sciences and the notions of cardinal importance in them.” (Encyclopedia 16)
A philosophical encyclopedia is a mechanism of selecting in and filtering out certain truths within a body of knowledge and in this way it is a system of thought not just “a collection of bits of information”. Hegel distinguishes a philosophical encyclopedia from an ordinary encyclopedia:
“The encyclopaedia of philosophy must not be confounded with ordinary encyclopaedias. An ordinary encyclopaedia does not pretend to be more than an aggregation of sciences, regulated by no principle, and merely as experience offers them. Sometimes it even includes what merely bear the name of sciences, while they are nothing more than a collection of bits of information. In an aggregate like this, the several branches of knowledge owe their place in the encyclopaedia to extrinsic reasons, and their unity is therefore artificial: they are arranged, but we cannot say they form a system. For the same reason, especially as the materials to be combined also depend upon no one rule or principle, the arrangement is at best an experiment, and will always exhibit inequalities. [Hegel encyclopedia 16)