Gut feeling - It just feels right
In a society as obsessed with the pursuit of pleasure as our own it is inevitable that people will believe that their emotions should rule their behaviour and of course, having feelings is part of being created in the image of God (Gn 1:27) but problems arise when they are made the sole basis for decision-making. They can be perverted as in the case of the sadist who derives pleasure from inflicting pain on others. They may disagree - witness the passion felt by those on both sides of the abortion debate, and they may change. The girl who wakes up with a hangover and pregnant after a one night stand knows with certainty that what 'felt so right' wasn't right at all. 'The heart is deceitful above all things' says Jeremiah (Je 17:9). It is no guide to ethical conduct.
Reason - It's logical.
If not the heart, why not then the mind? Can human reason be our basis for ethical decision-making? Part of the problem with reason as a tool for decision making is that reason never acts in isolation. For example in making a decision to treat a patient with pneumonia with antibiotics we are making a number of prior assumptions, not least that it is morally right to kill millions of bacteria in order to save the life of one sick person. Reason alone won't help us in finding the answers to questions like this. If the underlying assumptions we start from are wrong then we will reach the wrong conclusions even if our powers of reason are faultless our conclusions will be flawed - and whose powers of reason are faultless? Even the best of minds are not always reasonable. God gave us minds to think but reason also has its limitations.
Conscience - But I don't feel guilty
Our capacity to feel guilt is a reminder that we are fallen creatures, and there is no doubt that God can use conscience for our good. 'Train a child in the way he should go' says the writer of Proverbs (Pr 22:6). However conscience also has weaknesses as the only criterion for making moral choices. It may become blunted. Many of the Nazi doctors who presided over the killing of millions during the Second World War felt they had done nothing wrong. They were nonetheless judged to be guilty. On the other hand there is the danger that conscience may become oversensitive as in the case of the neurotic patient who is paralysed with feelings of guilt despite having committed no sin. Consciences also need educating. 'There is a way that seems right to a man but in the end it leads to death' (Pr 14:12). Men are capable of 'suppressing the truth' (Rom 1:18) and 'exchanging the truth of God for a lie' (Rom 1:25)
Consensus - Everybody's doing it
The desire not to appear different is a strong one, but majority opinion may not be correct. It was once believed that the earth was flat, that the sun revolved around the earth, that there was no connection between smoking and lung cancer. Every major scientific discovery initially has to challenge the status quo of incorrect consensus opinion. Furthermore popular opinion varies across cultures. Female circumcision is regarded as barbaric in England and civilised in parts of Africa - but opinions about abortion vary in the opposite direction. Consensus opinion may change over time within any one culture. Euthanasia for handicapped children, and the demented elderly is perfectly acceptable in Holland today, but during the Second World War many Dutch physicians willingly chose imprisonment in preference to being involved with it. Democracy may in fact just be a euphemism for mob rule. The Bible sternly warns us 'Do not follow the crowd in doing wrong... do not pervert justice by siding with the crowd' (Ex 23:2) Consensus opinion, after all, crucified Christ.
Consequences - The best outcome
This raises several questions, not least that the end does not justify the means. In the 1970s Pol Pot successfully eradicated leprosy from Kampuchea (a noble aim) but he achieved it by diabolical means (killing the leprosy sufferers). In our own society we are attempting to reduce the level of handicap by prenatal diagnosis and selective abortion. Is this justified? Considering outcome alone also ignores the fact that motives are important too? What of the person who does the 'right' thing for the 'wrong' reason? Also the consequences of actions can be very difficult to judge, in fact they may not become apparent until years afterwards. The heavy drinker does not have cirrhosis foremost in mind - nor does the promiscuous student consider that his actions may be leading to gonorrhoea or emotional hurt. The Bible is full of stories of entire nations who remained blind to the consequences of their actions until it was too late. So using outcome as our criterion also has limitations.
Relativism - What's true for you
This sounds a nice idea but let us think about it a moment. If there are indeed no absolutes then the statement 'there are no absolutes' can only be relatively true. Similarly to claim that 'all things are relative' is to make an absolute statement. This position is first and foremost logically absurd. But it is also unworkable in practice. Nobody in reality is a true relativist. Everyone makes moral judgments about others. No-one really sincerely believes that a belief that is diametrically opposed to his own can be equally true. Virtually every decision we make as individuals has repercussions for other people. If we were complete relativists we would be unable to make any objective decisions at all and we could certainly not be health professionals with this perspective. Right and wrong is not simply private prejudice.
Authority - What so-and-so says
In practice in the health-care team, the ultimate responsibility for ethical decisions often lies with the consultant. However there are problems with this. The presence of technical expertise and knowledge does not imply the possession of moral integrity. Just as there are politicians who cheat on their wives, embezzle funds and betray their countries so there are consultants who make decisions in their own rather than the patient's best interests. Even well-meaning people may be deceived or misinformed. We are all susceptible to being misled, deceived and having our judgment impaired by impure motives of which we ourselves may not be aware-'All a man's ways seem innocent to him, but motives are weighed by the Lord' (Pr 16:2). So whilst believing that all authorities have been instituted by God we mustn't fall into the trap of thinking that their decisions, even in their own areas of expertise, are therefore infallible. Doctors may possess God-like power and knowledge but it does not follow that they also have god-like character and judgment.
So where does this leave us? We are not discounting completely these means as guides in human conduct - but merely recognising their limitations. Emotions buzz and fade. Reason may fail or start from flawed premises. Conscience can be blunted, oversensitive or uneducated. Consensus is subject to prejudice and perversion. Consequences are often difficult to judge before the event and human authorities are not infallible.