The co-chairman of the world’s largest charitable foundation spoke up for foreign aid in his third annual letter because he says the world’s poorest won’t be visiting government leaders to make their case, unlike everyone else expecting budget cuts to their programs this year.

In the 24-page letter released Monday, Gates says not only is helping the poor with their medical needs and giving them the tools to be self-sufficient the right thing to do.

He says it’s also a good investment.

He outlines the ways helping people saves money over the long term: From cutting the cost to treat the sick by preventing their illnesses to increasing a child’s earning potential and future contribution to society education.