Residualism is the belief that unrealigned humans are only partly predisposed to evil..
"The good of human nature is threefold. First, there are the principles of which nature is constituted, and the properties that flow from them, such as the powers of the soul, and so forth. Secondly ... man has from nature an inclination to virtue. ... Thirdly, the gift of original righteousness, conferred on the whole of human nature .... The first is neither destroyed nor diminished by sin. The third was entirely destroyed through the sin of our first parent. But the second, the natural inclination to virtue, is diminished by sin."
Thomas Aquinas, Summa Theologiae 2:1:85:1, c.1274.
Antiresidualism is the belief that unrealigned humans are fully disposed to evil.
"Now the soul is not reborn if merely a part of it is reformed, but only when it is wholly renewed. The antithesis set forth in both passages [of John 3] confirms this. The Spirit is so contrasted with flesh that no intermediate thing is left. Accordingly, whatever is not spiritual in man is by this reckoning called carnal. We have nothing of the Spirit, however, except through regeneration. Whatever we have from nature, therefore, is flesh."
Calvin, Institutes, 2:3:1, 1536.
Residualism entails Integrationism, the belief that it is proper for God's' friends to unite with his foes, a principle that undermines real Christian practice. Consequently, Residualists see no need to seek separate accord with other Christianoids, instead joining undiscriminatingly with those they regard as God's foes.
This Integrationism (not to be confused with Integralism) was initially masked by extreme Statism, which enforced uniformity of Creed so that the question of relations between God's friends and foes was suppressed, and by Monasticism, which provided a spurious kind of alternative and separation for the "religious-minded". Liberalisation and secularisation have unmasked it.
Residualism is usually (as in the above Aquinas passage) accompanied by Additionalism (see on "Otherworldalism"), the belief that man's task is divided between this ("ordinary") world and the ("spiritual") otherworld. This enables Residualism to seem to accept the New Testament doctrine that defected humans are God's foes, while evading its gravity by seeing the enmity only in spiritual life, holding that our "spiritual" capacity has indeed been entirely ruined by the defection, but that our "ordinary" moral capacity is, perhaps diminished, but certainly intact, so that in ordinary life, even after the defection, a human can, without being realigned, choose well, and we can safely integrate with God's foes in mundane matters though not in religion.
Otialism (from Latin otium, leisure) is when so much is regarded as "ordinary" that Christianoidity becomes a mere leisure activity, akin to the "supporting" of a football team. Otialists blithely form business partnerships with wrongdoers, send their children to school with theirs, vote for them, and get their news from them. So their Christianoidity has no obvious effect on their everyday life, in which they are content to participate in the activity patterns of the society around them, carried along on the current of the prevailing culture; they are "conformed to this age" rather than being "transformed by renewal of mind" (Romans 12.2).
Protestant Residualism, accepting as its "lower storey" the Humanism of the surrounding culture, had by the 18th century degenerated to the point of Otialism, and remains so. This includes most of those who affirm "total depravity", which they reduce to a narrow question of the "mechanism" of realignment.
Papist Residualism, with Hellenism as its lower storey, has avoided the extreme of Otialism, though I gather that more recently it also has increasingly embraced Humanism, and recent Popes look increasingly like celebrities with fan bases. I hope at some point to consider this matter further.
Back to Bonhominalism.