CHICAGO — As so often, when I want to understand something about human nature, I open the pages of that great moralist, Samuel Johnson. Here, for instance, in his ''Rambler'' Essay No. 79, is a description of Ross Perot:
''To profess what he does not mean, to promise what he cannot perform, to flatter ambition with prospects of promotion, and misery with hopes of relief, to soothe pride with appearances of submission, and appease enmity by blandishments and bribes, can surely imply nothing more or greater than a mind devoted wholly to its own purposes, a face that cannot blush and a heart that cannot feel.''
Johnson, in this essay, is describing the suspicious man. He says that the man whose own tendency is to trickery suspects trickery in all around him. Mr. Perot, for instance, could not trust even his own teams of enthusiastic volunteers. He was extracting loyalty oaths from them, giving potential presidential electors letters of resignation to sign when they joined, so that he could ''accept their resignations'' the minute he was displeased with any of them. He was spying on the volunteers, in search of what (in naval terminology) he called ''hostile colors.''
He could not trust the professionals he had himself chosen. He felt the TV ad men they brought in were trying to overcharge him. The rich often think that everyone is after their money. But Mr. Perot's conspiratorial mentality goes beyond that, for reasons Johnson understood. It is the man who has cheated others who is obsessed with the thought of being cheated himself.
''Suspicion is, indeed, a temper so uneasy and restless, that it is very justly appointed the concomitant of guilt. It is said that no torture is equal to the inhibition of sleep long continued; a pain to which the state of that man bears a very exact analogy who dares never give rest to his vigilance and circumspection, but considers himself as surrounded by secret foes, and fears to entrust his children, or his friend, with the secret that throbs in his breast and the anxieties that break into his face. To avoid, at this expense, those evils to which easiness and friendship might have exposed him is surely to buy safety at too dear a rate.''
Mr. Perot's whole history is one of secrecy born of knavery. He refused to show his books to the government when contracting with the government. He said that the government was plotting to undo him -- though every other company in his position had shown the books.
Mr. Perot had things to hide -- the way he rose as a parasite on Texas Blue Shield, a predator on IBM, and a deceiver of the Social Security agency. He did not want anyone to know what he was up to. His employees were threatened with firing if they inquired after the salary of others in his company.
At Texas Blue Shield, Mr. Perot worked for the company in the morning, advising it on what computer programs to buy; then -- in the afternoon -- he sold Blue Shield the programs his fledgling company was developing. He later obscured his years of employment at Texas Blue Shield. When I asked him about them, he claimed he was just helping out a friend at Blue Shield.
The devious man suspects deception, as the deceived man becomes devious. It is a vicious circle, as Johnson realized: ''Men who are once persuaded that deceit will be employed against them sometimes think the same arts justified by the necessity of defense.'' Johnson, as usual, began his essay with a quote from a classical poet, in this case the Roman epigrammatist Martial, whose lines might be translated: Friend Gullible, so often taken in, Lacks our familiarity with sin.
Mr. Perot, familiar with the sins of duplicity and betrayal, saw them everywhere around him. This leads to a certain canny and shrewd toughness in a businessman, but it is totally incapacitating in one who calls for openness, dialogue and consensus in the public sphere. G.K. Chesterton, echoing Johnson, says it is better to be ''taken in'' by life than to live in perpetual fear of being cheated. Better to be taken in by life than left outside it, alone and omnidirectionally fearful. As the last lines of Johnson's essay put it, ''Better to suffer wrong than to do it, and happier to be sometimes cheated than not to trust.''
Garry Wills is a syndicated columnist.