Some people are accustomed to thinking that facts must either be believed or they must be

disbelieved—as if beliefs were like a light switch with only two positions, on or off. My use of the bathtub hoax is intended to illustrate that belief does not have to operate as a simple yes or no choice, all or nothing. Belief can be more conditional; it can be something that we decide to have "up to a point" or "to a degree". And so, the question we might ask ourselves while reading does not have to be "Should I believe 'it or not？" but instead can be "How much should I believe it？" This later question implies that the belief we have in any given fact, or in any given idea, is not determined by whether it sounds right or whether the source is an authority. It means that our beliefs are determined by the reasons that justify them.

Belief is not a mechanical action, brought about by invariable rules of nature. It is a human activity, the exercise of judgment. With this in mind, we might say that we perform. this action better when we know what the reasons are that have led to our belief, and why they are good reasons. These observations do not deprive us of our ability to believe in what we read. They are not intended to transform. you from credulous believers into stubborn doubters.

The process of weighing beliefs against the quality of reasons is one that you already go through all the time, whether you are aware of it or not. We all do. The practice of critical reading is the exercise of this kind of judgment on purpose. By doing it, we protect ourselves from being led into belief for inadequate reasons, but at the same time we open up our minds to the possibility of arriving at belief for adequate ones. If we decide to grant or withhold consent based on the quality of the reasons that we are given, we admit at the same time that two things are possible: We admit that we might consent less in the future if we discover that the reasons are not so good after all; and we admit that we might consent more if we are ever presented with better reasons than we had formerly known. This attitude is not pure skepticism any more than it is pure credulity. It is somewhere in between. It is the attitude of an open-minded thinker, of someone who wishes to be responsible for deciding for herself or himself what to believe.

The author's use of the bathtub hoax is meant to suggest that ______.

A．belief is nothing but a light switch

B．facts must be believed unconditionally

C．nothing should be believed or disbelieved

D．belief is more than a simple yes or no choice