TALL, bespectacled, and low-key, the man who runs the biggest single-country aid agency in the world believes that solving famine involves far more than shipping or even growing more food.
M. Peter McPherson, administrator of the United States Agency for International Development (AID), says the roots of famine reach much deeper into a basic hunger for new ideas, new skills, new research, new family planning programs, new health care, and new self-help initiatives.
As a political rather than a career appointee, he firmly represents the Reagan administration. Democrats in Congress have repeatedly pushed him and the President to act faster and to spend more money on feeding Africa's starving.
Acknowledging the pressure, he talks candidly about the difficulties of direct contacts with the pro-Soviet, Marxist government of Ethiopia. But he insists that more and basic progress could be made - if African governments and Western donors alike looked beyond emergency supplies and concentrated on long-term solutions, such as:
* More incentives from African governments to farmers to grow millet, sorghum , and other staple foods.
* Ending inefficient government monopolies on private buying and selling of grain.
* New research into high-yielding sorghum and millet seeds and ''much more work in dry-land (non-irrigated) agriculture.''
* Many more family-planning efforts. Fast-rising African populations are outpacing gains in food production year by year. Kenya's growth rate is the highest in the world - 4 percent a year - with its population of 19.4 million set to double to 38 million by the year 2000.
* More literate people. Irrigation systems along the Senegal River in the Sahel region are working at only 20 to 30 percent of capacity because local people are not yet able to manage or maintain them.
''The Marshall Plan worked in Europe because all the US had to do was send in resources,'' he says. ''Europe had the education, the skills. . . . Africa doesn't.''
* Better health care. Already Africans are living longer. Infant death rates are lower. But malaria is a recurrent threat and AID has brought together 500 people from 100 countries recently to look at developing new vaccines to defeat increasingly resistant malaria strains.
Is McPherson, a name known throughout the third world, optimistic or pessimistic about Africa?
''The record of what the world can achieve is written in Latin America and Asia,'' he replies. ''India is self-sufficient in food, after being almost destitute in the mid-1960s. South Korea has recovered remarkably. ''There's also been some progress in Africa, though the average American probably doesn't see it that way with all the current headlines about famine. . . . Personal income is up in some places. Once a person reaches five years old, he lives longer than before.
''What we have to do now is to concentrate, not just on welfare and guns, but on training and research.
''In the l970s, when resources began to flow from the richer nations, we concentrated on giving free medicines and free fertilizer . . . Often we didn't train people. We didn't create new technologies. We didn't encourage new African economic policies.
''If we now train and research, I think you could see a marked impact in Africa in 10 years. You won't get per capita income levels up to Asian or Latin American standards in that time. But you'll see progress.''