How does the author use foreshadowing in Crossing the River?

Hamilton, the slave trader, is not portrayed as a mean, vicious man, but rather, as very moral and proper in all matters except the commerce of bondage. We come to see Hamilton as a victim of the same system as the blacks from whom he buys blacks and the blacks whom he buys. His physical condition is better, of course, adorned with the niceties of English society, but the fate of his father foreshadows great emotional guilt and sorrow if he continues in his trade.