Think: A Compelling Introduction to Philosophy

by Simon Blackburn

The way in which implicatures are generated is part of the study of language called pragmatics, whereas the structure of information is the business of semantics.

Formal logic is great at enabling us to avoid contradiction. Similarly, it is great for telling us what we can derive from sets of premises. But you have to have the premises. Yet we reason not only to deduce things from given information, but to expand our beliefs, or what we take to be information. So many of our most interesting reasonings, in everyday life, are not supposed to be valid by the standards we have been describing. They are supposed to be plausible or reasonable, rather than watertight. There are ways in which such an argument could have true premises but a false conclusion, but they are not likely to occur.

The inference from what is true of one limited region of space and time to a conclusion true of different parts of space and time is called inductive inference. What Hume is bothered about has become known as the problem of induction.

Of course, Hume knows that we all learn from experience, and that we all rely upon the uniformity of nature. He thinks we share this natural propensity with animals. It is just that this is all it is: an exercise of nature. It is a custom or habit, but it has no special claim in reason. When we reason inductively there is a way in which our premises can be true and our conclusion false. Nature can change.

Getting this answer wrong is called the fallacy of ignoring the base rate.

‘conditional probability’.

Bayes’s theorem.

posterior probability of the hypothesis—

The ideal would be: the hypothesis is antecedently quite likely. The evidence is just what you would expect, given the hypothesis. And there are not many or any other probable ways the evidence could have come about.

We could now revisit a number of areas: the Zombie possibility, the design argument, the likelihood of a good God creating or allowing evil, and especially the discussion of miracles, using Bayes’s theorem. It is a tool of immense importance. The fallacies it guards against—ignoring the base rate, ignoring the chance of false positives—are dangerous, and crop up everywhere that people try to think.

Chance is just as good at throwing up improbabilities as design.

These represent the explanatory and simplifying ideals of science.

As a good psychologist should, he gives an explanation of the prejudice that we can argue a priori about cause and effect: We fancy, that were we brought, on a sudden into this world, we could at first have inferred, that one Billiard-ball would communicate motion to another upon impulse; and that we needed not to have waited for the event, in order to pronounce with certainty concerning it. Such is the influence of custom, that, where it is strongest, it not only covers our natural ignorance, but even conceals itself, and seems not to take place, merely because it is found in the highest degree.

The most perfect philosophy of the natural kind only staves off our ignorance a little longer.

What we have here is a splendid rejection of the rationalist ideal. In its place we seem to be left only with more or less familiar systems.

Thomas Kuhn (1922–96)

‘Normal’ science proceeds in the light of a set of paradigms, or implied views about what kind of explanations we should hope for. Periods of revolutionary science occur when the paradigms are themselves challenged. Science is to be seen as ‘a series of peaceful interludes punctuated by intellectually violent revolutions’. After the revolutions, our sense of what makes for a comfortable explanation of why things hang together changes.

Some people get quite excited quite quickly by this kind of thought. They take it to suggest a kind of ‘relativism’, whereby some people have their ‘paradigms’ and other people have others, and there is no judging which is better. Bu...

A scientific environment is (ideally) an environment in which the constant process of experimenting, predicting, and testing, weeds out the bad ideas. Only the ones that survive go on into the next generation. This is not to say that actual scientific environments are as ideal as all that: at any time science can no doubt boast its fair share of blinkers, prejudices, and distortions. But the process contains within itself the mechanisms of correction.

Science similarly contains within itself the devices for correcting the illusions of science. That is its crowning glory. When we come upon intellectual endeavours that contain no such devices—one might cite psychoanalysis, grand political theories, ‘new age’ science, creationist science—we need not be interested.

Galileo is here expressing what has become called the distinction between the primary and the secondary qualities of material things. The secondary qualities are the immediate objects of the senses: colours, tastes, sounds, odors, feels. According to Galileo they ‘hold their residence’ only in the sensitive (i.e. perceiving) animal. Moreover, according to Descartes, there is no reason for supposing them to ‘resemble’ whatever in nature causes them—the arrival of photons at the eye, in the case of colour, for example.

epiphenomenalism.

For a creature to flourish, it must get information from the environment that tallies with its actual needs. All that is necessary for this is that the information stimulates it to action in the right way.

We should not treat the data of the senses as straightforwardly conveying information about the real properties of things. This would be to treat confused data as if they were clear and distinct.

So as well as opening up dualism of mind and body Descartes and his contemporaries open up a dualism between the world as it is for us (sometimes called the ‘manifest image’)—the coloured, warm, smelly, noisy, comfortable, familiar world—and the world as it is objectively or absolutely (the ‘scientific image’)—the world that contains nothing but physical particles and forces spread out across the boundless spaces of the cosmos.

We can present an argument from relativity concerning tastes, odours, colours, sounds, and ‘feels’ like this: Suppose a part of the world or an object in the world displays a certain smell, etc. to one observer O. How it smells, etc. will be a function of O’s particular sensory structures. So, there will be or could be another creature O* with different sensory structures, to whom the same part of the world or the same object would smell, etc. quite differently. O and O* may each live equally efficient, adapted lives. So, there is no reason for saying that just one of O or O* has got the smells, etc. right. So, there is no one correct distribution of smells, etc. in the world. So, smells, etc. are better thought of as entirely mind-dependent.

The upshot of the argument is called ‘secondary quality idealism’. It gives us Galileo’s result that the qualities that are the immediate objects of sensory experience are driven ‘back into the mind’.

Pierre Bayle (1647–1706)

George Berkeley (1685–1753).

subjective idealism.

Berkeley and Hume deny that we can really understand the alleged properties of the alleged independent world, except in terms drawn from our own experience—our own minds.

Michael Faraday (1791–1867).

gambler’s fallacy.

It seems that our understandings are baffled in this too. We can have no conception of what it is for a law of nature to hold. We can understand the ways in which events do fall out, but never obtain any glimmer of a conception of why they must fall out as they do.

In the last section, following Faraday and Hume, we found that the ‘absolute’ scientific conception of an independent reality ran into problems of things versus their powers. We now find that our conception of those powers themselves, underwritten by laws of nature, is as frail as it could possibly be.

hut

Kant sees that when it comes to space and time, size, shape, and the objective order, to have a concept is not to have a mental picture. It is to have an organizing principle or rule; a way of handling the flux of data. Having the same organizing principles or rules could give us the same understanding of the world in spite of differences of subjective experience. The implication then is that we got into the problems of the last two sections because we were looking for ‘things’ to play certain roles: the role of objects standing behind and apart from powers and forces, or the role of something responsible for causal and physical laws. But if we can wean our understandings from this dependency on things, perhaps we can do better. Suppose instead we see thoughts of causation and law, things in space and time, and space and time themselves as necessary categories of thought. They provide us with a framework of principles with which to organize or systematize our experience. They do not provide a set of things we ‘infer’ from our experience.

The idea here is very similar to the ideas about the ‘self’ that we took from Kant, and indeed form the other side of the same coin. If we try to understand the self in sensory terms, as an object of experience, we meet Hume’s problem, that it is no such object. But if instead we think of the way a personal or egocentric standpoint organizes experience, the role of the self as an element in our thinking becomes clearer—and so do illusions engendered by that role.

‘transcendental idealism’.

The intention is not to deny some element of scientific understanding, or indeed common sense, but to explain how those elements hang together in our thought. It is those thoughts that structure what he calls the ‘phenomenal world’: the world that is both described by science, and is manifested to us in sense experience.

The question of whether, and how, Kant is successful is one of the great issues of modern thought.

A true realist or opponent of idealism wants to contend for facts and states of affairs that are entirely independent of the mind. The idealist constantly reminds us of the work of the mind in selecting and moulding our conception of the world we inhabit. The mind, for the idealist, creates the world we live in, the ‘Lebenswelt’ of our thoughts, imaginings, and perceptions.

The idealist tradition in philosophy stresses the inescapable and vital place that the shape of our own minds plays in ‘constructing’ the world as we understand it.

At the present time, cultural and especially linguistic factors are more prominent. We worry not so much about the subjectivity of experience as the variations of culture. So, many contemporary philosophers applaud a line of thought found in Wittgenstein: the so-called rule-following considerations. Wittgenstein considers the moment of understanding, when some concept is explained to us, and we realize ‘Now I can go on’ or ‘Now I know what is meant’. We seem to have grasped a rule or principle that separates correct application of a term from incorrect applications. This is a real feat.

But what shapes our minds one way or another? This is in fact the ancient topic, much pondered by Greek philosophers, of universals.

REALISM (sometimes PLATONISM).

CONCEPTUALISM.

NOMINALISM.

themes

the question of universals. The stakes are high, for at issue is our whole conception of our ability to describe the world truly or falsely, and the objectivity of any opinions we frame to ourselves. It is arguable that this is always the deepest, most profound, problem of philosophy.