Section B
Directions: There are 2 passages in this section．Each passage is followed by some questions or unfinished statements．For each of them there are four choices marked A, B, C and D．You should decide on the best choice.
Every once in a while the reasons for discouragement about the human prospect pile up so high that it becomes difficult to see the way ahead, and it is then a great blessing to have one conspicuous and undeniable good thing to think about ourselves, something solid enough to step onto and look beyond the pile.
Language is often useful for this, and music．A particular painting, if you have the right receptors(感受器), can light the spirits and hold them high enough to see a whole future for the race．The sound of laughter in the distance in the dark can be a marvelous encouragement．But these are uncertain stimuli, ready to work only if you happen to receive them, which takes a bit of luck.
I have been reading magazine stories about the technology of lie detection lately, and it occurs to me that this may be the thing I've been looking for, an encouragement supported by genuine, hard scientific data．It is promising enough that I've decided to take as given what the articles say, uncritically, and to look no further.
As I understand it, a human being cannot tell a lie, even a small one, without setting off a kind of smoke alarm somewhere deep in a dark recess of the brain, resulting in the sudden discharge of nerve impulses, or the sudden outpouring of neurohormones(神经激素) of some sort, or both．The outcome, recorded by the lie-detector device is similar to the responses to various kinds of stress.
Lying, then is stressful, even when we do it for protection, or relief, or escape, or profit, or just for the pure pleasure of lying and getting away with it．It is a strain, distressing enough to cause the emission of signals to and from the central nervous system warning that something has gone wrong．It is, in a pure physiological sense, an unnatural act.
Now I regard this as a piece of extraordinarily good news, meaning, that we are compelled to be a moral species at least in the limited sense that we are biologically designed to be truthful to each other.
It seems a petty thing to have this information, but perhaps it tells us to look again, and look deeper．We are indeed a social species, more dependent on each other than the celebrated social insects．We can no more live a solitary life than can a bee．We are obliged, as a species, to rely on each other．Trust is a fundamental requirement for our kind of existence and without it all our linkages would begin to snap loose.
It is enough, quite enough, to know that we cannot even tell a plain untruth, betray a trust, without scaring some part of our own brains.
In the first paragraph, the author implies that ______.