I have some advice while reading philosophy: the most important thing is not determining whether the philosophy is consistent with your pre-existing beliefs, but whether you can disengage from your own beliefs, suspend them for the moment, and be able to explain these philosophical theories in your words.
Initially, philosophy is an attitude of reflection. Any activity that involves reflection at a length is usually described as “philosophical,” whether that includes establishing formal concepts or just talking about how one justifies a certain belief they hold.
As a matter of fact, reflection requires a mental fortitude most of us do not have, because of how we are raised and taught up till adulthood. That entails a level of understanding we call common sense, which means we believe the way things are because that is supposed to be the case. Common sense knowledge is encapsulated in a certain type of language, a mode of communication we learn by practice and constant use.
The greatest obstacle to understanding philosophy or concepts in philosophy, or philosophical language, is usually our commitment to common sense reasoning. Common sense is usually a great mechanism for the basic activities we are engaged in daily, no doubt. Yet this entails a large amount of assumptions that are not examined, and they are taken for granted.
Nothing is wrong with common sense, at one level. But since it contains a great number of assumptions, it can entrench certain prejudices in the mind and affix a mentality that doesn’t suffer skepticism or careful analysis very well.
Also, for many, the language of common sense is very comfortable because the speaker/writer and the listener/reader participate in an understanding of shared meaning. Words and phrases are repeated almost continuously and that reinforces common sense. However this shared meaning, composed of everyday words an phrases, is not precise – for words are ambiguous and are dependent on context.
In philosophy this comfort level is stripped bare when the focus of analysis is directed at the very words we take for granted. In a new and rather strange context, these words are no longer familiar, and no longer seem practical. But in the long run, philosophy enhances how a person thinks, or at least it demonstrates how to analyze and break down some form of thought. This is only an initial step, and for more, I discuss strategies of thought here.