Aristotle’s Causes

Aristotle 384-322 BC Student of Plato (429-327) Teacher of Alexander (353-323) Founded ‘Lyceum’ We have his lecture notes Posterior Analytics Physics

Aristotle Theory of knowledge Not skeptical Use of reason and dialogue on experience

Forms Aristotle rejected Plato’s theory of Forms ‘Third Man’ argument We recognise Bob as a man because he participates in the Form of Man We recognise the Form of Man as the Form of Bob because both have something in common Both participate in a further Form of Man – the Third man. We recognise the Third Man as a Form of Man because of a Fourth Man …

Episteme Knowledge of the world or scientific knowledge Is knowledge of facts like ‘Bob is a man’ Satisfies the fundamental condition: We suppose ourselves to possess unqualified scientific knowledge of a thing [when] we know the cause on which the fact depends, as the cause of that fact and of no other, and, further, that the fact could not be other than it is Note: Plato would also have agreed with this The Forms were his ‘causes’

Explanations By cause we really mean explanation If one knows the cause of X one is able to explain it If one can explain X then one knows its cause An explanation is the answer to the question ‘why is S a P?’ where S is the subject and P is a property. Why is Bob a man?

Explanations What explains why S is P? Look at the standard ‘syllogism’ in his Logic Socrates is a Man All Men are Persons Socrates is a Person This justifies believing that Socrates is a Person It also explains why Socrates is a Person (S is P)

Explanations Take any argument of the form S is M M is P S is P We can say: Why is S a P? Because S is M and M is P To find an explanation we just need to find the right M (called the Middle Term) to go between S and P

Explanations Note 1: The conditions on knowledge are satisfied in virtue of explanations being in the form of valid deductions Note 2: Such deductions have to satisfy certain other conditions to prevent triviality and to make them real explanations They are then called demonstrations

Explanations So: Why is Bob a man? We have: Bob is M M is a Man Bob is a Man

Explanations So: Why is Bob a man? We have: Bob is a Builder a Builder is a Man Bob is a Man The reason is, because Bob is a Builder and all Builders are Men

Causes Aristotle proposes 4 types of cause Material The statue is brown because it is bronze Formal The statue has legs because it is the image of a man Effective The statue looks like a man because the bronze was poured into a man-shaped mould Final The statue was made because it honours Pericles

Scientific Knowledge For each demonstration the premisses also require explanation The demonstrations that constitute episteme Form a structure of linked deductions Each link in the chain of deductions is such that the causes are more general than the subject and predicate being explained

Intuitions The problem of purely deductive knowledge: Chain of premises and conclusions is endless Episteme is impossible Chain is circular Knowledge has no foundation First premises exist They are not knowable by demonstration

Intuitions First premises are known by induction from sense data Therefore we must possess a capacity of some sort [for getting knowledge without demonstration.] ... And this at least is an obvious characteristic of all animals, for they possess a congenital discriminative capacity which is called sense-perception.

Intuitions First premises are known by induction from sense data But though sense-perception is innate in all animals, in some the sense-impression comes to persist, in others it does not. So animals in which this persistence does not come to be have either no knowledge at all outside the act of perceiving, or no knowledge of objects of which no impression persists; animals in which it does come into being have perception and can continue to retain the sense-impression in the soul.

Intuitions First premises are known by induction from sense data And when such persistence is frequently repeated a further distinction at once arises between those which out of the persistence of such sense-impressions develop a power of systematizing them and those which do not. So out of sense-perception comes to be what we call memory, and out of frequently repeated memories of the same thing develops experience; for a number of memories constitute a single experience.

Intuitions First premises are known by induction from sense data From experience again – i.e. from the universal now stabilized in its entirety within the soul, the one beside the many which is a single identity within them all – originate the skill of the craftsman and the knowledge of the man of science, skill in the sphere of coming to be and science in the sphere of being.

Intuitions First premises are known by induction from sense data Thus it is clear that we must get to know the primary premises by induction (epagoge); for the method by which even sense-perception implants the universal is inductive.

Intuitions First premises are known by induction from sense data Now of the thinking states by which we grasp truth, some are unfailingly true, others admit of error – opinion, for instance, and calculation, whereas scientific knowing and intuition (noûs) are always true: further, no other kind of thought except intuition is more accurate than scientific knowledge, whereas primary premises are more knowable than demonstrations, and all scientific knowledge is discursive.

Intuitions First premises are known by induction from sense data From these considerations it follows that there will be no scientific knowledge of the primary premises, and since except intuition nothing can be truer than scientific knowledge, it will be intuition that apprehends the primary premises – a result which also follows from the fact that demonstration cannot be the originative source of demonstration, nor, consequently, scientific knowledge of scientific knowledge.

Investigations Episteme is a structure of demonstrations Leading upwards from more general to more particular truths Giving the causes of things Based on undemonstrated conceptual truths We discover the bases through intuition How do we discover the demonstrations?

Investigations Collect facts of appearances (phenomena) It is owing to their wonder that men both now begin and at first began to philosophize; they wondered originally at the obvious difficulties, then advanced little by little and stated difficulties about the greater matters, e.g. about the phenomena of the moon and those of the sun and of the stars, and about the genesis of the universe. The senses are generally reliable It is their function to tell us about the world

Investigations Consider reputable opinions (endoxa) As in other cases, we must set out the appearances and run through all the puzzles regarding them. In this way we must test the credible opinions about these sorts of experiences – ideally, all the credible opinions, but if not all, then most of them, those which are the most important.

Investigations Apply dialectic (elenchus/Socratic Method/…) Dialectic is useful for philosophical sorts of sciences because when we are able to run through the puzzles on both sides of an issue we more readily perceive what is true and what is false.

Investigations Apply dialectic (elenchus/Socratic Method/…) Furthermore, it is useful for uncovering what is primary among the commitments of a science; for it is impossible to say anything regarding the first principles of a science on the basis of the first principles proper to the very science under discussion, since among all the commitments of a science, the first principles are the primary ones.

Investigations Apply dialectic (elenchus/Socratic Method/…) This comes rather, necessarily, from discussion of the credible beliefs (endoxa) belonging to the science. This is peculiar to dialectic, or is at least most proper to it. For since it is what cross-examines, dialectic contains the way to the first principles of all inquiries.