Conscience A* grade summary notes


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Aquinas’ theory of the conscience

  • Aquinas’ theory of the conscience involves his theory of natural law ethics.
  • God gave us reason (ratio).
  • Reason has a power called synderesis which allows us to first know the synderesis rule (or ‘key precept’) and then the primary precepts.
  • The ‘synderesis rule’ is that we have the tendency to do good and avoid evil.
  • The primary precepts are to protect and preserve human life, educate, reproduce, live in an orderly society and worship God.
  • It also has a power called conscientia, which allows us to apply the primary precepts to moral actions/situations and figure out what we should do.
  • Conscience is the whole process of synderesis and conscientia together.
  • Our reason knows which actions are good and which are bad, and causes us to feel guilty if we do something we know to be bad.
  • We shouldn’t feel guilty for all bad things we do though – if we do bad due to ignorance but we couldn’t have known better, then that’s not our fault. Aquinas calls that ‘invincible ignorance’ – ignorance that could not have been prevented.
  • If we do something bad out of ignorance, but we could and should have known better, then that is our fault. Aquinas calls that ‘vincible ignorance’ – ignorance that could have been prevented.


  • Aquinas is overly optimistic about human nature when he claims that it has an orientation towards the good. Look at the terrible things humans have done throughout history, e.g. slavery and Nazism. If synderesis really existed in our nature, we should not expect to find the extent of moral evil that we do.
  • Psychological accounts of human behaviour seem more accurate, such as that our moral views result from our social conditioning. Skinner argued this.

Defence of Aquinas:

  • Aquinas isn’t saying that humans will do more good than bad though, nor that humans will never do horrendously terrible things.
  • Aquinas thinks we are corrupted by original sin and he even thinks entire cultures can be corrupt. That’s probably how he would explain Nazism.
  • It’s possible for us to have an orientation towards the good and yet completely fail to act on it. So the fact that humans do terrible things does not counter Aquinas’ theory.

Alternatively: use Karl Barth’s critique of Aquinas

  • Karl Barth thinks Aquinas is dangerous for relying on human reason. Reason is corrupted by original sin and is therefore dangerously unreliable. 
  • Christians should only have faith in the Bible and that’s all. We shouldn’t use our reason to try and figure out right and wrong.

Freud’s theory of the conscience

  • Freud thinks that what we call ‘conscience’ is really just the result of the way we are raised to control our animalistic instincts. 
  • He claimed there are three parts to the human mind:
  • The Id is our unconscious instincts
  • The Ego is our conscious self-aware decision-making self
  • The Super-ego is our mind’s memory of the social rules (our society’s morality) conditioned into us by authority figures during childhood
  • The conscience is just the interaction between these three parts of the mind.
  • E.g. there’s a desire for food which bubbles up from the Id into the Ego, so you become aware of wanting food. However, your Super-ego tells you that it’s class-time right now, so you can’t eat. You then have to choose whether to obey your ego and feel frustrated or give in to your Id and feel guilty about breaking society’s rules.
  • This explains conscience without reference to anything supernatural like God.
  • Freud’s theory of psycho-sexual development. Freud thought children had to learn to control the Id in stages. If self-control is not learned at each stage, it can lead to problems later in life.
  • Oral stage – the stage at which babies learn to interact with the world through putting things in their mouth.
  • Anal stage – children must learn to control going to the toilet – they can control too much or little.
  • Phallic stage – Oedipus/Electra complex develops
  • Latency stages – 6-puberty – gender roles learned, sexual desire develops and is learned to be controlled/repressed.
  • Mature genital stage – Controlled sexual desires result in a desire for love and marriage. A person now has a fully developed conscience where the ego controls the Id with reference to the superego.

Evaluation of Freud:

  • Freud is not a proper scientist – he didn’t do any real experiments, he studied a small sample size of people who were not a good cross-section of society.
  • Because of this, Popper (inventor of falsificationism theory) said Freud’s theories were ‘unfalsifiable’ – not real science. There was no way to prove them wrong because they were not based on reality.

Defence of Freud’s general ideas:

  • Piaget was a real scientist and basically defended Freud’s general idea that the conscience is just the result of the way we raise children.
  • Freud might have been unscientific in many of his ideas, but the claim that conscience is the result of conditioning/socialisation is scientifically accurate according to Piaget.

The issue of cross-cultural moral disagreement

  • This is a criticism of Aquinas and a strength/argument for Freud. 
  • If Aquinas was right that all humans are born with the ability to know the primary precepts, shouldn’t we all agree about what is right and wrong? 
  • In reality, we disagree – and the disagreement tends to fall along cultural boundaries. Different cultures have very different ideas about what is right/wrong.
  • This suggests Freud’s theory is correct – that our moral views come from the society we are raised in – not some innate ability to discover a supposed natural moral law.


  • Although there are very different moral views in different societies, there is still a core set of moral views that all cultures have in common. 
  • No culture allows killing or stealing for no reason. Education and reproduction is valued in all cultures.
  • These are very similar to the primary precepts – suggesting Aquinas’ theory actually is correct.


  • However, these cross-cultural moral similarities can be explained by the practical requirements for a society to exist and not fall apart. If a society allowed killing or stealing, it would fall apart. 
  • So, it’s no surprise we find rules against killing and stealing in all societies. A society which allowed these things for no reason would not be able to exist for long.
  • This is a simpler explanation than the idea that the conscience came from God, so Freud’s scientific approach is more convincing than Aquinas’ theological approach.