Because, Because, Because, Because:
An Analysis of Aristotle's
Structure of Causal Explanation.   

Jonah Bossewitch
PHI 301
Professor Sarah Broadie
October 26, 1995

	The concept of causality lies at the heart of our ability to draw inferences about the world around us.  Without this concept we would be forced determine which  events are associated with each other simply by observing regularities.  This would severely cripple our ability to make correct inferences and would probably result in our eventual  extinction.  Imagine how difficult it would be to figure out why stubbing your toe immediately preceded incredible pain, not to mention  more life threatening inferences, without the heuristic of causality.  Even the dog who moves his food bowl out of the rain probably has at least an implicit notion that the rain is causing his kibbels to get wet.  In spite of the fact that causality is foundational to so many aspects of cognitive processing, it is still the subject of heavy philosophical dialogue.  It therefore comes as no surprise that Aristotle had a fair share of thoughts on the topic. 
	For Aristotle, the discussion of causality naturally followed the discussion of change.  Once he has described the types of change that can occur and how they occur, it is logical to proceed to the question 'On account of what [do they occur]?'  This question actually asks for the explanation of a thing, and not just the cause of a thing.  In the sense we have been using it, the cause of event e_1 , is a preceding event e_2 , which brings about e_1  in accordance with some law.  While a causal account for an event can serve as its explanation, there are other types of explanations that also correctly answer the question 'On account of what?'  Aristotle's primary concern in Physics II  is a taxonomy of these various types of explanation.  
	The first distinction that Aristotle makes is between natural changes and unnatural changes.  "Some things are due to nature; for others there are causes." (Physics II.1, 192b9)  By this he does not intend to imply that some things happen without a cause.  Rather, as he soon clarifies, "nature is a sort of source and cause of change and remaining unchanged."  (Physics II.1, 192b21)  Aristotle recognized that every change must have an explanation, and points out that not all changes can be explained in the same way.  Things that have a nature are "things which have in themselves a source of their changes... are not themselves natures, but are due to nature." (Physics II.1, 193b4)  In other words,  Aristotle is stressing the difference between causes that originate within an object, versus those causes that originate outside of an object.  Things with natures may still be effected by external forces, but they also may be effected from within.  It is crucial to draw this distinction between these two type of processes since the type of explanation will vary depending on which one is operating.
	Aristotle clearly feels that natural change is far more important than unnatural changes.  He seems to regard unnatural changes as if they are trivial since he thinks it is simple to discern an external cause.  Furthermore, contrary to many modern philosophers, he believes that all chains of external causes eventually terminate.   This means that for all change is ultimately rooted in natural causes.  Consequently, Aristotle concentrates his efforts on understanding natural change and spends a considerable amount of energy dispelling illusions created by other apparent causes.
	Always the teacher, Aristotle casts the enumeration of the types of explanation into a lesson.  "For it certainly is a problem, if there are two sorts of nature, [form and matter] which of them the student of nature is concerned with... Up to what point, then, should the student of nature know the forms of things and what they are?" (Physics II.2, 194a15, 194b10)  He responds to this by listing the various components of an explanation that together make up a complete answer to the question 'On account of what?'.  An explanation lacking one of these components might be incomplete, so a student who does not inquire into all of these aspects will never gain a thorough knowledge of the thing being investigated.

	"These are the causes, and this is how many there are.  They are four, and the student of nature should know about them all, an it will be his method, when stating on account of what, to get back to them all: the matter, the form, the thing which affects the change, and what the thing is for." (Physics II.7, 198a22)  These four categories have been named the material cause, the formal cause, the efficient cause, and the final cause respectively.  While modern day commentators argue over the best translation of 'aitia' they all unanimously agree that it is not cause.  Jonathan Lear prefers to refer to the four causes as the four fashions in which we cite the cause.  This interpretation helps prevent us from grossly misrepresenting Aristotle's views on this subject.  

See Jonathan Lear, Aristotle: The Desire to Understand.

	(1) Material Fashion: "That out of which as a constituent a thing comes to be." (Physics II.7, 194b23)  This fashion of explanation is the most straightforward as it is simply the elements that a thing is made of.
	(2) Formal Fashion:  "This is the account of what the being would be."  (Physics II.7, 198a27)  According to Lear, this can be best understood as the order of the essence.  This aspect of explanation attempts to answer the 'On account of what?' question by appealing to the overall structure and the defining principle of a thing, namely it's form.  Since something's  form is the way it behaves (i.e. things behave in accordance with their forms), a thorough understanding of a thing's form will explain its behavior.   
	(3) Efficient Fashion: "The primary source of the change or the staying unchanged... and in general that which makes something of that which is made, and that which changes something of that which is changed." (Physics II.7, 198a30)  This fashion is best understood as an active version of (2).  In this explanation we find the form doing what the form does best - forming.  Lear argues that the title of this fashion is misleading since Aristotle's concepts of cause and effect are different from our own.  In Aristotle's conceptual world things have causes, not events, causes are not required to be prior events, and causes and effects were simultaneous.  This makes it difficult, if not impossible, to fully equate any of the four fashions with our own fashions of explanation.
	(4) Final Fashion:  "A thing may be a cause as the end... And anything which, the change being effected by something else, come to be on the way to an end."  (Physics II.7, 198a32)  This is the place where Aristotle naturally finds the teological explanation of a thing.  Since the end state of a thing is its form (or is a component of a thing's form)  the student should once again investigate the form in order to discover a thing's telos.  This purpose provides the fourth and final fashion of explanation for natural change.
	Aristotle is quick to point out that "The last three often coincide.  What a thing is, and what it is for, are for the most part one and the same, and that from which the change originates is the same in form as these."  (Physics II.7, 198a25)  It is clear from the explanations above that the three latter fashions all exemplify different aspects the form.  It is puzzling that Aristotle first introduces four causes only to reduce their number to two a few pages later  (after the last three collapsed into one).  We can speculate that he does this to emphasize the fact that although there are only two sources of natural change, matter and form, an explanation is still incomplete unless the four causes are enumerated.  Even though the last three are all manifestations of form, they are different enough to be considered separately.
	Although the examination of the explanation of natural change is complete, many questions still remain.  What about things that are not natural (have no nature) - how do they change?  Are there any sorts of explanations other than the four (two) enumerated in Book III, or can all forms of explanation be reduced to these?  How should a natural scientist go about obtaining the information that Aristotle demands? 
	Aristotle's treatment of unnatural changes focuses primarily on the teological aspect of change.  His examples of Luck, the Automatic, and necessity all share a lack of purpose in stark contrast to natural change.  The necessary is the most general of these three cases since the Automatic might have occurred for the sake of something and Luck is a special case of the Automatic.  If a thing comes to be of necessity it is without a purpose, and it follows that this thing must be formless.  Aristotle infers from this that matter must be the source of necessity, and also infers converse, "the necessary in things which are natural is that which is given as the matter, and the changes it undergoes." (Physics II.9, 200a31)  It seems as if unnatural things are a degenerate form of natural things since they are made up of matter without form.  Consequently, Aristotle does not need to describe any alternative fashions of explanation since all other types of explanations are subsets of the four fashions.    
	Aristotle also believes that unnatural things can not bring about changes that violate the nature of a thing.  "But there are two sources of natural change, of which one is not natural, since it has no source of change in itself.  Anything which changes something else without itself being changed is of this latter sort." (Physics II.7, 198a36)  From this we see that the worlds of the natural and the unnatural interact, but they do not collide.   External changes might not originate in a nature, but the changes they cause must be in accordance with a things nature (if it has one).  Aristotle is cleary more interested in expanding his knowledge of the natural than in exploring the unnatural.  He would have found it extremely odd that modern scientists concern themselves solely with matters of necessity and view all change as unnatural.   
	In contrast to modern philosophers of science, Aristotle does not seem particularly worried about the epistemological issues surrounding theories of explanation.  How to determine if an alleged cause is the actual cause is not an issue which can be ignored.  This gap is especially glaring when it comes to teological explanation.  Even if you accept his idea that natural events can have a telos, Aristotle suggests no way to confirm a teological hypothesis.  Perhaps in his day there were few competing hypothesis that did not seem absurd so there was no impetus to develop a method of discriminating between ideas.     
	Although the Aristotelian concepts of causality and explanation do not directly correspond to any of our own concepts there is still much to learn from his treatment of the subject.  Most of his arguments are internally consistent and force us to reexamine our own concepts from a new critical perspective.  Although his concepts are often alien, it is easy to draw analogies from his ideas to modern ones that shed new light on both.  The two things that have not changed since Aristotle's time are the difficulty and the importance of understanding the nature of causality.  Aristotle's account of causality is a very impressive acheivment that can provide us with tremendous insights into its nature.