Say rather that he is old, for he does not exactly see himself as especially wise most of the time. Even though he may provide the occassional nugget of wisdom from time to time if asked for his oppinion upon this or that matter.

"Feel free to do so, and if it helps assuage the guilt somewhat know that if I'm left without much to do for too long a time I grow antsy and jittery. So helping you would be helping myself as well." He says, eyes sparkling with amusement. "Far be it for me to make a person go against their own nature, however, so I shant try to convince you to do otherwise if that is what you feel you need to do. But you don't really need to do much to pay me back. Treat me to an occassional meal and conversation and this old man would count the debt paid in full."