A French foreign legion general must make a trip across the deserts of Tunis to a remote outpost. He must travel on foot from the nearest town, and the distance is such that it will take a person six days to cover it.

The problem is that a person on foot can only carry enough water and provisions to last him four days. The general can take with him any number of assistants to help him carry the supplies, but they must be fed as well, and cannot be left stranded in the desert.

How will the general make it across, and how many assistants will he need to help him? (Find the smallest number.)