Concept

Conscience

Intro

Conscience is the faculty by which a person judges his own actions as right or wrong, and experiences that judgment as binding rather than optional. Two features make it philosophically interesting, and both are easy to miss because the experience is so ordinary.

It addresses you. Conscience does not present moral information the way memory presents facts. It accuses, approves, insists and will not be talked out of things on schedule. People describe it in the second person without noticing they are doing so, as something that speaks, condemns, or will not leave them alone. Whatever the correct explanation, the phenomenon has the shape of being addressed by someone rather than of consulting a database.

It resists the will. You cannot vote yourself innocent. A person can change his stated moral views far more easily than he can change what his conscience does about a particular act he committed. This is why conscience is evidence of something rather than merely a report of upbringing: pure social conditioning ought to be revisable by the same social pressure that installed it, and conscience frequently is not.

Christianity's account is that conscience is part of what it means to be made in God's image: a created capacity, genuinely one's own, through which the moral law written into human nature is apprehended. Paul states it directly, saying that Gentiles who do not have the law show the work of the law written on their hearts, their conscience bearing witness and their thoughts accusing or defending them (Romans 2:14-15).

Two clarifications keep the doctrine from being overstated, and both are in the tradition rather than concessions to critics. Conscience is not infallible: it can be badly formed, misinformed about facts, or deadened by repeated violation, which is what Paul means by a seared conscience (1 Timothy 4:2). And it is not the moral law itself, only the faculty by which the law is registered. Treating conscience as the standard rather than the receiver produces the modern confusion in which sincerity substitutes for being right.

Quick reply line: "Conscience is not a rulebook you consulted, it is something that argues with you and usually wins. You can change your opinions about morality far more easily than you can change what your conscience does with what you actually did. That asymmetry is the thing that needs explaining."

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In full

Conscience is the practical moral faculty: the application of moral knowledge to particular acts, whether prospectively as obligation or retrospectively as approval and accusation. The Greek term in the New Testament is syneidēsis, literally a knowing-with, carrying the sense of a co-witness to one's own conduct; see G4893 - syneidesis. The Latin conscientia preserves the same construction.

The concept does substantial work at three levels: in moral theology, where it governs the duty to act on one's best judgment; in the theology of general revelation, where it is the principal mode by which moral obligation reaches those without special revelation (see General Revelation and Sensus Divinitatis); and in apologetics, where the phenomenon grounds the argument developed at Argument from Conscience.

The biblical account

• Written on the heart. Romans 2:14-15 is the foundational text. Gentiles without the Mosaic law nonetheless do by nature what the law requires, showing its work written on their hearts, with conscience as co-witness and their reasoning alternately accusing and defending. This is the scriptural basis for holding that moral knowledge is universal while special revelation is not.
• A witness that can testify against the self. Paul appeals to his own conscience as an independent witness (Romans 9:1), which only makes sense if it is not simply his preference.
• It can be weak. In 1 Corinthians 8 and 10, a conscience insufficiently instructed produces genuine but mistaken scruples, and Paul's instruction is to respect it rather than override it, because acting against conscience is itself a sin (Romans 14:23).
• It can be damaged. 1 Timothy 4:2 describes a conscience seared as with a branding iron, and Titus 1:15 describes a defiled one. The faculty is corruptible by use, which is exactly what a moral capacity in fallen creatures should be expected to be.
• It can be cleansed. Hebrews 9:14 and 10:22 present the cleansing of conscience as an accomplishment of Christ's work, not of moral effort. This is the point where the doctrine stops being philosophy and becomes gospel.

The scholastic distinction

Medieval theology separated two things that English collapses into one word, and the distinction resolves most of the puzzles about conscience being both authoritative and fallible.

• Synderesis, the habitual grasp of first moral principles, that good is to be done and evil avoided. On Thomas Aquinas's account this cannot be extinguished, though it can be obstructed.
• Conscientia, the act of applying those principles to a particular case. This is a judgment, and like any judgment it can be mistaken, because it depends on reasoning and on the facts believed.

So conscience is infallible in its root and fallible in its operation. A man may hold correctly that the innocent must not be harmed and conclude wrongly that a particular person is not innocent. The error is in the minor premise, not in the moral principle, which is why moral formation is largely a matter of getting the facts and the reasoning right rather than acquiring new first principles.

The erring conscience

The hardest question in the classical treatment: what should someone do whose conscience is mistaken?

Aquinas's answer, which has largely held, is that one is bound to follow conscience even when it errs, because to act against one's judgment that something is wrong is to choose what one believes to be evil. But an erring conscience does not excuse, where the error is culpable, that is where the person could and should have known better.

The two-sided result is uncomfortable and correct. Sincerity is not sufficient, because a sincerely held wrong judgment can still be blameworthy in its formation. And sincerity is not nothing, because acting against conscience is wrong even when conscience is wrong. This is why the tradition insists that conscience must be formed, by scripture, by instruction, by the community, by attention to the facts. A conscience is more like a trained ear than an infallible oracle.

Objections

"Conscience is just internalised social conditioning, so it tells you about your culture and nothing more."

The strongest version of this is Freud's, on which conscience is the superego, the internalised voice of the father and of social prohibition (see Sigmund Freud). Three replies:

1. It explains content, not authority. Grant that the specific content of moral judgment is heavily shaped by upbringing. What conditioning does not explain is why the judgment presents as binding, or why guilt is felt as being owed to someone rather than as fear of exposure. A conditioned preference should feel like a preference.
2. It fails on the reformers. Conscience routinely condemns the culture that formed it, which is the mechanism of every moral reform movement. Abolitionists were not reporting their society's values back to it. On the conditioning account, this is the one thing conscience should never do.
3. It is a genetic account, and genetic accounts do not settle truth. Explaining how a belief was acquired leaves entirely open whether it is correct.

"Cultural variation shows there is no universal moral sense."

Variation is real but shallower than the objection needs. What varies is chiefly the scope of application, who counts as a neighbour, and the factual beliefs feeding the judgment, rather than the underlying principles. Nearly every culture condemns murder, treachery and cruelty to one's own; they differ on who is included in "one's own". C.S. Lewis documents the convergence in the appendix to The Abolition of Man, gathering parallel precepts from Egyptian, Babylonian, Hindu, Chinese, Greek, Roman, Norse and Jewish sources.

"Evolution explains moral emotions, so no further explanation is needed."

An evolutionary account of the mechanism is compatible with the mechanism tracking something real, in the same way that an evolutionary account of vision does not make what you see illusory. The debunking version of the argument, that selection would produce these feelings whether or not any moral facts existed, is a serious argument, and it is engaged at Sharon Street and Atheist Moral Realism Defeater. Its cost is that it debunks the objector's own moral convictions along with everyone else's.

Apologetic deployment

• It is the most portable argument available, because it needs no shared authority and no scientific background. The interlocutor already has the data.
• Ask about a specific memory, not about morality in general. People will defend relativism in the abstract and abandon it about something they actually did. The move is to shift from "is morality objective" to "what was that, when you could not sleep".
• Do not claim atheists lack conscience. The Christian claim is the opposite: everyone has it, because everyone bears the image. See Imago Dei.
• Land on cleansing, not on guilt. The argument's purpose is not to leave someone convicted. Hebrews 9:14 is where it goes.
• Know the limit. Conscience gets you to a moral authority that is personal and not identical with the self. It does not get you to the Trinity. Overclaiming here invites a fair objection.

See also

• Argument from Conscience, the structured argument built on this phenomenon
• Morality, the definitional anchor
• Divine Command Theory, the account of obligation conscience registers
• General Revelation, the doctrine conscience belongs to
• Sensus Divinitatis, the parallel innate awareness of God
• Imago Dei, the anthropology grounding a universal moral faculty
• G4893 - syneidesis, the Greek term and its semantic range
• Original Sin, why the faculty is damaged rather than merely undeveloped
• Thomas Aquinas, the synderesis and conscientia distinction
• Martin Luther, conscience captive to the word of God
• John Henry Newman, conscience as the aboriginal vicar of Christ
• C.S. Lewis, the cross-cultural convergence of moral precepts
• Sigmund Freud, the principal reductive account
• Sharon Street, the evolutionary debunking challenge
• Atheist Moral Realism Defeater, engagement with the debunking argument
• Euthyphro Dilemma Objection Defeater, the metaethical objection cluster