Where do you draw the line?

[N]o sooner do we depart from sense and instinct to follow the light of a superior principle, to reason, meditate, and reflect on the nature of things, but a thousand scruples spring up in our minds concerning those things which before we seemed fully to comprehend. Prejudices and errors of sense do from all parts discover themselves to our view; and, endeavoring to correct these by reason, we are insensibly drawn into uncouth paradoxes, difficulties, and inconsistencies, which multiply and grow upon us as we advance into speculation, till at length, having wandered through many intricate mazes, we find ourselves just where we were, or, which is worse, sit down in a forlorn Skepticism.

– George Berkeley, The Principles of Human Knowledge

In daily life, we assume as certain many things which, on a closer scrutiny, are found to be so full of apparent contradictions that only a great amount of thought enables us to know what it is that we really may believe. In the search for certainty, it is natural to begin with our present experiences, and in some sense, no doubt, knowledge is to be derived from them. But any statement as to what it is that our immediate experiences make us know is very likely to be wrong.

– Bertrand Russell, The Problems of Philosophy

The passages above describe eloquently an idea that has long lingered troublingly in the back of my mind, but remained unarticulated due to principally to my own laziness in fleshing it out. I don’t expect to exorcize all of my demons on the subject here, but at least it will be a start.

I’ve never perceived myself as being the type to fall easily into one camp or another on things. Consequently, I either find myself taking a position of devil’s advocate in order to participate in a conversation, or find myself sinking into a disappointed indecision. If I’m around conservatives, for example, I usually feel myself inexorably being pulled in the opposite direction. When around liberals, the opposite is true.

In either instance, I am left wondering, “how can this or that person be so sure about himself or herself?” Furthermore, I wonder, “how can I be so unsure of myself?” Granted, I may be objecting to attitudes more than to opinions in the aforementioned examples, but the questions still remain unanswered.

It’s not that I lack the ability to construct a logical argument and follow through on the conclusion. But on what basis are such conclusions ultimately derived?

Consider the following question: Is abortion right?

Now consider the following two answers to this question:

– Life begins at conception.
– The taking of a life is wrong.
– Abortion takes a life.
– Therefore, abortion is wrong.

Fine, but what about this:

– A fetus is part of a woman’s body.
– A woman has a right to do with her body as she pleases.
– Therefore, if she wishes to have an abortion, she is justified.

They are both simplified examples to be sure, and while I’m no logician, they suit my purposes here. There appears to be no problem with the arguments themselves; the rub lies in the assumptions. Then we are forced to ask: which assumption is right? That just leads to another argument, founded on other, more basic assumptions.

But if we keep digging, what eventually remains? I wonder how often people stop to ask themselves this question. It seems possible that one could rely on “sense and instinct” clothed in the type of arguments above without ever considering the soundness of their assumptions. For practicality’s sake we must we draw a mental line somewhere if we are to avoid a slippery slope that leads to relativism or worse. We can’t go around denying the existence of tables all day long. But where and when should that line be drawn?