The Analogy of Religion

Philosophy, Christian Theology, and Joseph Butler

Month: April, 2012

Foundation of all Knowledge

In part one of Descartes’ Mediations, the famous philosopher embarked on a method of systematic doubting. Every belief that could be doubted, for any reason at all, was dispensed with. Descartes refused to affirm even beliefs that seemed to be obviously true – a task which he found he struggled to do. To help him systematically doubt even these beliefs, he imagined a supremely powerful demon who was deceiving him at every point. Using this tool, Descartes even manages to doubt that he knows simple mathematical beliefs such as two plus three equals five.

While this leaves Descartes in a state of discontent, nonetheless, he presses on:

I will, nevertheless, make an effort, and try anew the same path on which I had entered yesterday, that is, proceed by casting aside all that admits of the slightest doubt, not less than if I had discovered it to be absolutely false; and I will continue always in this track until I shall find something that is certain, or at least, if I can do nothing more, until I shall know with certainty that there is nothing certain.”

Descartes is determined to believe nothing unless it cannot be doubted, even if these leaves him with no knowledge at all.

But no matter how much Descartes doubts, he cannot doubt one thing: “So that it must, in fine, be maintained, all things being maturely and carefully considered, that this proposition (pronunciatum ) I am, I exist, is necessarily true each time it is expressed by me, or conceived in my mind.”

Even while Descartes doubts, the very fact that he is doubting proves to himself that he must exist. It is this truth: “I am, I exist” that Descartes builds his knowledge on.

In the search for knowledge, then, we have seen three different approaches to knowing that which is, the stable objects of knowledge. For Plato, knowledge is by recollecting pre-existing knowledge; for Aristotle, knowledge starts with sense perception; for Descartes, knowledge starts with what is indubitable – that is, what is impossible to doubt.

A lot more could be said about each of these Philosopher’s epistemology, but for now these posts will hopefully of provided us with the background for the introducing Joseph Butler’s Analogy of Religion.

Is Descartes’ starting point for knowledge reasonable?

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Rene Descartes: Doubts, Demons and Despair

Rene Descartes, the French 17th century philosopher, had a huge impact on the field of Epistemology. His Meditations on First Philosophy is required reading for anyone who wishes to understand the nature of knowledge.

In recent times, a number of films have posed us questions about the nature of knowledge. The Matrix placed us in a computer generated virtual reality, and asked us if we could tell the difference between “the real world and the dream world”, to paraphrase Morpheus. Inception, the impressive 2010 heist film, also asked the same kind of question: can we know our experiences actually reflect external reality and that we are not merely dreaming?

These questions are not new for philosophers; similar thought experiments, no doubt, go all the way back to Ancient Greece. However, Descartes brought these questions to the forefront of the philosophical thinking of his day.

Aristotle, if you recall in his Posterior Analytics, claimed that the starting-points of knowledge are sense-perception, memory and the ability to gain knowledge of the universals. These starting points are known by “intuition” and not demonstration (a logical argument). Ask Aristotle how we could sure we were not dreaming, and he would (probably) say that it is by intuition that we know that we perceive the real world. But Descartes’ answer is very different.

In Meditations* part one Descartes starts of with some observations about his Philosophical education:

I first became aware that I had accepted, even from my youth, many false opinions for true, and that consequently what I afterward based on such principles was highly doubtful

Descartes observes that many of the opinions he once had he now knows are not true, and, moreover, the basic principles which these opinions were based on are doubtful. So he resolves to “demolish everything completely and start again” and to “at length apply myself earnestly and freely to the general overthrow of all my former opinions”.

At this point, Descartes explains his methodology: ” it will not be necessary for me to show that the whole of these are false”, or in other words, Descartes doesn’t intend to prove that all his opinions are not true. Instead, he deems it necessary to “withhold belief from what is not entirely certain and indubitable”. Or in other words, If there is any reason to doubt a belief than Descartes will not affirm it.

But because any one person holds to numerous beliefs it would be impossible to doubt them all. Instead, Descartes goes for the very foundations of these beliefs. First he doubts the senses and all beliefs derived from them because they have sometimes been unreliable. In Descartes own words:

All that I have, up to this moment, accepted as possessed of the highest truth and certainty, I received either from or through the senses. I observed, however, that these sometimes misled us; and it is the part of prudence not to place absolute confidence in that by which we have even once been deceived.”

But what about seemingly obvious beliefs such as ” I am in this place, seated by the fire, clothed in a winter dressing gown, that I hold in my hands this piece of paper”? To doubt these type of beliefs Descartes recalls that he has such experiences in his dreams: “How often have I dreamt that I was in these familiar circumstances, that I was dressed, and occupied this place by the fire, when I was lying undressed in bed?”

What do we know then?

Descartes suggests we might have mathematical knowledge such as two plus three equals five because this appears to be true whether we are dreaming or not. But perhaps God is making me go wrong every time I try to answer a sum, says Descartes. After all, he continues, God allows us to be deceived sometimes, so why not all the time? He writes:

“…perhaps Deity has not been willing that I should be thus deceived, for he is said to be supremely good. If, however, it were repugnant to the goodness of Deity to have created me subject to constant deception, it would seem likewise to be contrary to his goodness to allow me to be occasionally deceived; and yet it is clear that this is permitted.”

What is there was no God? Then we are in a no better situation, says Descartes. As then, “I reach the state in which I exist, whether by fate, or chance, or by an endless series of antecedents and consequents, or by any other means, it is clear (since to be deceived and to err is a certain defect ) that the probability of my being so imperfect as to be the constant victim of deception“.

But all these doubts are not enough for Descartes. For he can not get rid of “those old and customary opinions perpetually recur– long and familiar usage giving them the right of occupying my mind, even almost against my will”. Try as he might, he cannot make himself doubt everything. So to counter balance “the distorting influence of habit”, he goes on the offensive:

I will suppose, then, not that Deity, who is sovereignly good and the fountain of truth, but that some malignant demon, who is at once exceedingly potent and deceitful, has employed all his artifice to deceive me.

And Descartes ends part one with the determination to mediate on this supposition in order not to believe anything false at all. It should be noted that Descartes does not actually believe that a demon exists, instead he continually thinks about the possibility to counter act his so-called habitual opinions. That is how I interpret the point of Descartes’ demon.

And so ends this fully packed post. Find out how Descartes tries to escape from his method of systematic doubting next time.

Should we doubt all our beliefs? What do you think about Descartes method?

*John Cotteringham, who specialises in the study of Descartes work, has a translation which is much more readable, but not freely available online. He also provides extracts from Descartes work in his Anthology of Western Philosophy, which has been a helpful study aid.

I Just Know! Aristotle and Sense-perception

Aristotle, you will recall in yesterday’s post, has shown us one way of knowing something: through a demonstration or argument. This seems like a relatively straight forward way of knowing. However, Aristotle’s second way of knowing (which actually forms the foundations for demonstrations) is a little tricky to grasp, and probably far more controversial. In fact, in a few weeks time we shall explore Descartes’ attack on the broad idea of “Pre-existing knowledge”, which will probably make this idea of Aristotle’s easier to understand too. Let’s start with a phrase Aristotle writes near the beginning of his Posterior Analytics: “All teaching and all intellectual learning arises from pre-existing knowledge”

At first glance Aristotle appears to be following Plato’s lead by suggesting that all knowledge is pre-existing (see my earlier posts on the Meno). However, this is not an affirmation of innate knowledge; Aristotle certainly doesn’t mean that. What he means by pre-existent knowledge is knowledge which is “primary and immediate”; or, in other words, knowledge gained by an innate power or capacity. It is this capacity that gives us knowledge, for example, that “All men are moral”.

Why doesn’t Aristotle think that we have innate knowledge of true premises? He writes “it would be strange if we possessed [these starting-points] all along, since then we would possess knowledge superior to demonstration without being aware of it.” Nevertheless, Aristotle is aware of Meno’s paradox and the problem of coming to know something without pre-existing knowledge of it: “it is clearly impossible…..for us to acquire [these starting-points] if we are ignorant and have no predisposition for knowledge”.

His solution is “an innate power of discernment – what we call sense-perception”. For Aristotle, when we perceive particulars, such as a man called Bob, and then a man called Derek and then many other particular men, our memories retain these perceptions and forms what Aristotle calls “experience”. From this experience we now have a “universal” in our minds: the universal of man to be precise.

Let me put it another way: If we perceive a man called Bob, a “primitive universal” of man is in our minds, and if we continue to perceive particular men the universal of man is more and more firmly established in our minds. And this provides some of the knowledge that the premise “All men are mortal” is true. The objects of knowledge, then – the universals – are perceived by naturally noticing and remembering similarities between the particulars. The same would apply to the universal of women, the universal of potato…etc…

Finally, Aristotle says that this innate capacity to acquire pre-existing knowledge is more accurate and more sure than the scientific knowledge that proceeds from it. Aristotle says “there cannot be scientific knowledge of the starting-points…it is intuition that grasps the starting-points”. Or to point it another way: sense-perception, memory and the ability to gain knowledge of the universals cannot be demonstrated; these capacities are assumed to be true from the start.

We still don’t know much about this “intuition” and how it functions, but Aristotle’s’ key point is this: some knowledge you can’t prove with any argument or “demonstration”, but this knowledge is still more sure than the arguments which build on it.

In my next post – and leaping ahead hundreds of years in the history of ideas – I will explain how Descartes attempts to doubt these starting-points. Furthermore, he will try to demonstrate that they are true!

Does Aristotle’s idea of innate capacities solve Meno’s Paradox? What do you think about the idea of sure knowledge which doesn’t require an argument to believe?

Cold Hard Logic: Aristotle and Demonstrative Knowledge

Aristotle’s works, as I mentioned in my last post, were not written in the form of dialogues (any dialogues he did write have apparently been lost). Instead we have works that are very dense and technical, which makes Aristotle hard to read and understand. The Posterior Analytics is no different in this regard, but since it is a relatively short work it provides us with a useful introduction to Aristotle’s philosophy and a chance to hear some of  his ideas about the nature of knowledge.

We have already heard how Plato’s defined knowledge: he said that knowledge related to that which is. Plato, moreover, thought that the objects of knowledge are the immaterial, unchanging and eternal forms (remember the form of “absolute beauty”). The objects of everyday experience do participate in the forms, according to Plato, but they themselves are only the objects of opinion, not knowledge. Building on Plato, Aristotle also thinks that knowledge must relate to what is stable and unchanging: he writes “knowledge relates to what cannot be otherwise.” But Aristotle does not shared the contention that the objects of knowledge are the forms and he also denys that we have innate knowledge in the sense Plato expresses in the Meno. The reason for this will become apparent in the next post, but first we will briefly explore another element of Aristotle’s epistemology: demonstrative knowledge.

Demonstrative or Scientific knowledge

Aristotle describes two ways of knowing. The first is pre-existing knowledge and the second is through a demonstration. Take the following argument:

1. All men are mortal

2. Socrates is a man

3. Therefore, Socrates is mortal

For Aristotle, a “demonstration” is an argument with two characteristics. First, the premises need to be true. That ‘all men are mortal’ must be a true statement and that ‘Socrates is a man’, likewise, must be knowledge (remember knowledge and truth relate to “what cannot be otherwise”). If the argument is logically valid and the premises are true then the conclusion must be true too. Both characteristics seem to be fulfilled by the argument above. The following argument, however, is invalid, but it does have true premises:

1. All men are mortal

2. Socrates is an animal

3. Therefore, Socrates is mortal

Notice that the conclusion does not follow from the premises. In contrast,take this argument:

1. All men are purple

2. Socrates is a man

3. Therefore, Socrates is purple

The argument is valid (the conclusion follows from the premises), but one the premises is clearly not true.

Aristotle calls a valid argument with true premises a “scientific syllogism” and  the conclusion “scientific knowledge”. Now the word ‘science’ obviously has a specific modern meaning, but remember for Aristotle – writing before the advent of the modern scientific disciplines – the word refers to knowledge in this broader sense.

Demonstrative knowledge, then, is knowledge gained through a logical argument. But then another question arises: how do we know whether a premise, “All men are mortal”, in this example, is true? What are the starting points for knowledge which these premises are built on? With this in mind, I will explore Aristotle ideas about sense perception, memory and the building blocks of knowledge in my next post.

Does Aristotle’s two characteristics of a demonstration seem reasonable to you? Do you agree with Plato and Aristotle that knowledge must relate to that which is or what cannot be otherwise? Why does knowledge need to relate to stable objects?