Some may take offense to the number of assumptions that are within this series, but you can't come to any logical conclusion without use of a few presuppositions.
Although one should minimize assumptions as much as possible, there are many things in this world that simply cannot be proven or disproven. In these instances, it is necessary to assume one way or the other. For instance, as much as Rene Descartes wished to avoid presuppositions, his most popular philosophical argument -"cogito ergo sum," or "I think, therefore I am" - is based on the assumption that it takes an existing person to think. To a degree, I am being ridiculous with this idea, but that's exactly my point.
You cannot prove this to be true, but you readily accept it because to assume otherwise is unthinkable. Similar situations occur throughout our entire life, yet we don't notice. This trend is not a nuisance; rather, it is a quite necessary activity to reach any meaningful conclusion.
In geometry (the most logical of mathematics), we have certain ideas we call postulates. These are statements we assume to be true. From these assumptions, mathematicians crafted many theorems, including the Pythagorean Theorem. We don't doubt the Pythagorean Theorem because it's based on assumptions. Why then does it become wrong when we do the same about other aspects of life?
It's not as if we have any alternative that offers a worldview without assumptions. Even the simplest concept, like Descartes' famous maxim, are built upon other assumptions and presuppositions.
The question is which assumptions are better. What should we take by faith? This is the purpose of this Apologetics series.