[109] Bhikkhus, there are these four kinds of trees. What four? The softwood (pheggu) tree surrounded by softwood; the softwood tree surrounded by heartwood (sāra); the heartwood tree surrounded by softwood; and the heartwood tree surrounded by heartwood. These, bhikkhus, are the four kinds of trees. In just the same way, bhikkhus, there are these four kinds of persons comparable to trees found existing in the world. What four? The one of softwood surrounded by softwood; the one of softwood surrounded by heartwood; the one of heartwood surrounded by softwood; and the one of heartwood surrounded by heartwood.
And how, bhikkhus, is a person one of softwood surrounded by softwood? Here, bhikkhus, a certain person is immoral, of evil character, and his company (parisā) too is immoral, of evil character. It is in this way, bhikkhus, that a person is one of softwood surrounded by softwood. Just as, bhikkhus, that softwood tree is surrounded by softwood, so, bhikkhus, I say this person is comparable to it.
And how, bhikkhus, is a person one of softwood surrounded by heartwood? Here, bhikkhus, a certain person is immoral, of evil character, but his company is virtuous, of good character. It is in this way, bhikkhus, that a person is one of softwood surrounded by heartwood. Just as, bhikkhus, that softwood tree is surrounded by heartwood, so, bhikkhus, I say this person is comparable to it.
And how, bhikkhus, is a person one of heartwood surrounded by softwood? Here, bhikkhus, a certain person is virtuous, of good character, but his company is immoral, of evil character. It is in this way, bhikkhus, that a person is one of heartwood surrounded by softwood. Just as, bhikkhus, that heartwood tree is surrounded by softwood, so, bhikkhus, I say this person is comparable to it.
And how, bhikkhus, is a person one of heartwood surrounded by heartwood? Here, bhikkhus, a certain person is virtuous, of good character, and his company too is virtuous, of good character. It is in this way, bhikkhus, that a person is one of heartwood surrounded by heartwood. Just as, bhikkhus, that heartwood tree is surrounded by heartwood, so, bhikkhus, I say this person is comparable to it.
These, bhikkhus, are the four kinds of persons comparable to trees found existing in the world.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.