(FORTUNE Magazine) – For decades, ideologues of the left and right have been talking past each other about how to eliminate poverty. In a timely new book entitled Rethinking Social Policy, Northwestern University sociologist Christopher Jencks -- a self-described egalitarian liberal with the soul of a conservative -- marshals rigorous scholarship to cut through the cant on poverty, race, and the so- called underclass. Jencks shows how the system has failed: It doesn't deliver enough money, as liberals charge, yet it reinforces the dependency and destructive social patterns conservatives decry. Stronger economic growth alone won't help much. To repair the damage will require both an improved social safety net and more self-reliance on the part of the poor. Jencks spoke with FORTUNE's Louis S. Richman.

The first thing we must do is to build programs that reward behavior the society believes in. Society has every right to insist that recipients of public support work and be law-abiding. When taxpayers are convinced that the welfare system is discouraging work, they have a right to be upset. The values of the poor are no different from those of other Americans. Almost all welfare mothers want to get a job and would seize the opportunity if they could count on having the additional help they need to support their families. The widespread impression that a lot of recipients cheat is accurate. But cheating is understandable when regulations force people to do it. Given a choice between reporting your earnings to the authorities or seeing your family go hungry, almost everyone would cheat. Welfare recipients need a more reasonable set of rules. A successful policy has to begin by abandoning the myth that poor families can support themselves entirely by working. Unskilled single mothers can't support their families on $5 an hour. A proper antipoverty agenda would reward work effort instead of penalizing it. The poor should be encouraged to take any work they can find as a first step to gaining experience in the labor market. The overwhelming majority of welfare recipients could probably find such jobs now -- without expensive training programs. The problem is, most of the low-wage jobs for which they are qualified do not pay enough for a worker to support a couple of kids. Our current policies pull the rug out from under those who would try to become more self-reliant by accepting low-paid employment. Instead of finding themselves on a path out of poverty, they see their benefits withdrawn and usually end up worse off ((see table)). They need the added incentives and security of continued income support, a greatly expanded earned income tax credit, affordable health insurance, and child care vouchers. ''Workfare'' experiments now under way in several states are a step in the right direction, but they offer too little carrot and too much stick. Those who succeed often lose the housing subsidies, health benefits, and child support they need once they take a job. A better approach would supplement low earnings with continued public support. Raising the minimum wage looks cheaper, but it passes on to employers the cost of ensuring that every worker can support a family. That's an inefficient and inequitable way to fight poverty. Ultimately, we would be better off doing away with the minimum wage, allowing more low-paid jobs to be created, and supplementing the wages of workers with families who take these jobs. A bigger problem will be to end the social isolation that keeps the poorest Americans trapped in inner cities and depressed rural areas. Building public housing has never been a very promising approach. Its one advantage is that no one else has to live near the poor. The trouble, of course, is that it forces the poor to live near one another. The best strategy to help them escape is to increase the use of housing vouchers, which would allow poor families to live where they want. If we don't want to see America's inner cities descend further into a Hobbesian state of crime and drugs, we will also need to halt the continued flight of responsible working people. More residents should have a personal stake in their well-being. One incentive worth trying would be subsidized mortgage rates that would allow more poor working families to become homeowners. Welfare is costly but not staggeringly so. The $34 billion we spend on federal Aid to Families With Dependent Children, Medicaid, and food stamps is a small part of the national budget. For a new approach that encourages work effort to succeed, government will, for a time, probably have to spend more -- not less, as many of the ''reformers'' evidently hope.

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