In the Mahabharata, Bhishma lectures Yudhisthira about the types of friends a ruler has. Basically, he talks about (1) “natural” friends, who share a similar temperament with you or belong to your family, (2) friends whose ancestors have been loyal to your family, (3) friends with whom you share a relationship of mutual profit, and (4) “contrived” friends, who you can pay to follow you. Then he talks about a rare class of friends — the dharmatma (“righteous soul”). Though everyone may wish to have a few righteous friends, they are not someone you can easily search for. Also, once you find them, they are not permanent. Because they are detached, they may move away if you leave your virtuous path, as the scripture suggests.
After raising general concerns about the trustworthiness of friends from the first four classes, Bhishma gives features of friends you can trust: (1) they are happy to see you happy and sad to see you sad, and (2) they are never jealous of your progress but get alarmed in your adversities. Unsurprisingly, trustworthy friends form a class of their own.
Based on this model, Karna appears to comfortably qualify as a trustworthy friend for Duryodhana. But is he a righteous friend as well? This is not an easy question to answer. A key given in the text is that you have to be a righteous soul yourself to attract a righteous soul as your friend. Accordingly, no matter how good a person Karna was, the scripture may hesitate to label a friend of Duryodhana as “righteous.” Only a king like Yudhisthira deserves a dharmatma as a friend.
So how would you grade Karna’s friendship? Please feel free to share your views in the comments section.