## An elementary precept of logic says that where there are two propositions, P and

An elementary precept of logic says that where there are two propositions, P and Q, there are four possible "truth values," P~Q, Q~P, P&Q, ~P~Q, where ~ means "not."   Do people ever apply this to pairs of philosophy propositions? For example, has anyone applied it to positive and negative liberty, or to equality of opportunity and equality of condition, or to just process and just outcome? On these topics I can find treatments of the first two truth values but none of the second two.   If this precept of logic is not applied, has anyone set out the reasons?

### I'm not entirely sure I

I'm not entirely sure I follow, but perhaps this will be of some use.

Whether two propositions really have four possible combinations of truth values depends on the propositions. Non-philosophical examples make the point easier to follow.

Suppose P is "Paula is Canadian" and Q is "Quincy is Australian." In this case, the two propositions are logically independent, and all four combinations P&Q, P&~Q, ~P&Q and ~P&~Q represent genuine possibilities. But not all propositions are independent in this way; it depends on their content.

P and Q might be contradictories, that is, one might be the denial of the other. (If P means that Paula is Canadian and Q means that she is not Canadian, then we have this situation.) In that case, the only two possibilities are P&~Q and ~P&Q.

Or P and Q might be contraries, meaning that they can't both be true though they could both be false. For example: if P is "Paula is over 6 feet tall" and Q is "Paula is under 5 feet tall," then we only have three possibilities: P&~Q, ~P&Q, and ~P&~Q. The fourth case, P&Q, isn't possible.

Or P and Q might be subcontraries, meaning that they can both be true, but can't both be false. For example: if P is "Paula is under 6 feet tall" and Q is "Paula is over 5 feet tall," then the only possibilities are P&Q, P&~Q and ~P and Q. ~P&~Q isn't possible.

Or P might imply Q. If P is "Paula is over 6 feet tall" and Q is "Paula is over 5 feet tall," then the possibilities are P&Q, ~P&Q, and ~P&~Q. Here, P&~Q isn't possible.

Finally, P and Q might be equivalent. Suppose P is "The temperature is 32 degrees Fahrenheit" and Q is "The temperature is 0 degrees Celsius." In that case, P and Q are in effect the same proposition, expressed by different sentences. They are either both true or both false, leaving P&Q and ~P&~Q as the only possibilities.

All of this applies across the board, and in particular it applies in philosophy. Not all philosophical claims are independent, and so for some philosophical propositions, one or more of the four combinations won't represent possibilities. But at least some philosophical disputes are over the very question of what the logical relationship between two claims actually is. For example: consider "Paula's behavior is determined" and "Paula is responsible for her behavior." One important view is that these are contraries; they can't both be true. Other philosophers deny this, claiming, for example, that responsibility entails determinism, in which case "Paula is responsible, and her behavior is not determined" doesn't represent a genuine possibility. Other philosophers would claim that the two are independent, and so all four combinations represent genuine possibilities.

This kind of disagreement about the logical relations among philosophical claims is common in philosophy. But the larger point is that we can't simply assume in all cases that all four combinations represent genuine possibilities.

## Some philosophers hold views that assert A, and some others, nonetheless called

Some philosophers hold views that assert A, and some others, nonetheless called philosophers, the contrary of A. Then isn´t that not just all about the domain of opinion? Some of them well argumented, wise and logically consistent, while others are less so. So can we just say when people think, reflect about things, then they are doing philosophy? Or please tell me the difference that distinguishes one person thinking from one making philosophy. Because if so I feel like that the field "philosophy" is a passepartout word and therefore not really useful or worthy of beeing discipline, it´s just what everyone does in greater or lesser depth (thinking)...and I think I´m wrong.

There are disagreements in many areas of thought, not just philosophy, and historians, physicists, classicists and so on all argue with each other much of the time. The people who work in these areas are all thinking, but philosophers are generally thinking about thinking itself, and not directed at a particular subject matter, which distinguishes the discipline from others. So they are not all doing philosophy at all.

## Have you ever changed your mind about a major philosophical problem or theory

Have you ever changed your mind about a major philosophical problem or theory and did you feel that it was a waste of time defending your previous position?

Yes. No. The time I spent defending my previous position -- against what I now regard as decisive objections -- helped me to see why a different position is more plausible, and it helped me to adopt the new position without having to worry that I hadn't given my previous position a fair shake.

## Is "doing" philosophy a series of back and forth arguments? If so, then just who

Is "doing" philosophy a series of back and forth arguments? If so, then just who is the jury that decides? If a group of experienced analytic professors debates one Ayn Rand follower with no academic training, and repeated population samples find the Randian more convincing, then just who is right?

If so, then just who is the jury that decides? ...then just who is right?

As I see it, those two questions don't go hand-in-hand. Which side in a debate has the better reasons isn't something that a jury (in any sense of 'jury') can decide. It's not like legal guilt, which is something that a jury (or its equivalent) must decide and which isn't guaranteed to match what a fully informed and impartial observer would decide. No one is legally guilty unless a jury (or its equivalent) decides that he/she is. But one side in a debate can have the better reasons even if everyone in the audience judges otherwise. I think this point holds for debates in general, including philosophical debates. That's one reason why the oft-repeated "Who's to say?" is the wrong question to ask when debating an issue in ethics: no one's say-so is necessary or sufficient for truth in ethics or in philosophy more generally.

The idea that the consensus, or even the unanimity, of an audience doesn't determine the quality of a debater's reasons goes back to the ancient dispute between Plato and the sophists about the nature and value of philosophy and rhetoric. Much has been written about that topic, including much that's available online.

## Which branches of philosophy are more likely to be made redundant due to

Which branches of philosophy are more likely to be made redundant due to advances in science, and which ones are more likely to endure despite major advances in science? Joe W.

If we could answer your question, we would be able to predict the future direction of science. But science is full of surprises. Moreover, what gets called "science" (or math or logic) and what gets called "philosophy" is to some degree arbitrary. I don't think disciplinary boundaries are very important. What I do think is important is the questions themselves. So why not ask the questions and not worry about whether they are "science" or "philosophy"?

## Can studying philosophy make one's life worse? I've been reading philosophy in

Can studying philosophy make one's life worse? I've been reading philosophy in my spare time for the last four years and it has not improved any facet of my life other than make me more critical of everything and most philosophers living or dead except for a handful. It has not led me to "wisdom" in the slightest and it has made me more argumentative with others in a sort of shallow legalistic sense.

Can studying philosophy make one's life worse?

Certainly it can, just as working out to get fit can make one's life worse: one who works out to get fit can thereby tear a hamstring and become laid-up and miserable, or thereby suffer a heart attack, etc. Indeed, working out to get fit can make one's life worse overall, i.e., all things considered. Ditto for studying philosophy. There's no reason to think otherwise.

But studying philosophy, or working out to get fit, can also make one's life better, including better overall. For many people, myself included, studying philosophy has improved their lives overall (although I began studying philosophy because of an intense curiosity about the issues it covers rather than because of a conscious desire to make my life better by studying it). I doubt I can say anything more helpful without knowing more about your own encounters with philosophy. For instance, by "more critical of everything," do you mean "more intellectually vigilant about everything" or "more negative and cynical in my attitude toward everything"? I see the former as a benefit, even if the latter isn't. I'm also curious to know which philosophers you've been reading and which of them belong to the handful about whom you're not critical (in whichever sense of "critical"). Without knowing more about you, all I can say is that my own experience of studying philosophy has been positive overall, which is fortunate since I can't realistically see myself doing anything else with the bulk of my time. I'd urge you not to give up on philosophy. If you'd like to contact me, my email address appears on my homepage.

## People trying to defend philosophy often point out that the natural sciences (

People trying to defend philosophy often point out that the natural sciences ("natural philosophy") grew out of it. Does that really recommend philosophy, or does it just mean that we use the word "philosophy" much differently now than in Newton's time? Is it at all likely that philosophy as it is practiced today will result in the creation of significant new disciplines?

nice question! hard to predict of course ... but some might say that psychology and now cognitive science have partly grown out of 'philosophy' fairly recently ... and some would argue that philosophy is essential for the continued development of cognitive science .... but more importantly (and perhaps you're sensitive to his), one might probably make the case for the value of philosophy intrinsically, i.e. philosophy is valuable in itself, not (merely) in terms of what other (good) things it might produce -- after all, the 'creation' of new disciplines, even if it can legitimately be assigned to philosophy, is a relatively rare thing -- and hard to justify centuries of philosophizing by saying every half a millennium or so it sloughs off a new discipline .... So better to look for your defense of philosophy elsewhere!

hope that's useful ... great question!

ap

## As practicing philosophers, how do you react to known academics and

As practicing philosophers, how do you react to known academics and intellectuals who are dismissive of philosophy, like Stephen Hawking and Lawrence Krauss? Are there some truths to what they are saying about the nature and value of philosophy?

Speaking just for myself, I react much as I did in answering Question 4636 and Question 4759. For reasons that I hope those answers make obvious, I don't regard the dismissive remarks of Hawking, Krauss, Dawkins, Tyson, and their ilk as worth taking seriously. As far as I can tell, their remarks stem from simple ignorance of philosophy, often coupled with ineptitude at it.

## Can anybody who thinks about philosophical qustions become a philospher?

Can anybody who thinks about philosophical qustions become a philospher? Likewise, is it necessary to have an academic background in philosophy to be considered a philospher?

Great questions! Certainly, "philosophy" can be understood as an academic discipline. After all, there are graduate degrees in philosophy that are offered by academies in most countries around the world; there are official philosophical organizations such as the American Philosophical Association and the Royal Society of Philosophy; there are official philosophical journals, conferences, and sites on the web such as aksphilosophers, and so on. But philosophy as a practice, can be traced back before there were academies and universities, journals and official international philosophical associations. Arguably, it was philosophy that gave rise to there being academies rather than vice versa --for it was Plato, in the fourth century BCE, who founded the first academy. So, yes, one can be philosophical and practice philosophy without being part of some official academy, and in fact many well known philosophers in the early modern era did not hold positions as professors in academies --Hobbes, John Locke, Spinoza, John Stuart Mill, and more.

I suggest the best way to explore philosophy is to dive into the works of philosophers from Socrates, Plato, and Aristotle..... and to explore the awesome resources that make philosophy accessible to all, such as the Stanford Encyclopedia of Philosophy or this site and its links at no cost. It is my hope that you might also find institutions like colleges, universities, societies, reading groups in your area... where philosophy is practiced in a community of inquiry...in which people are engaged in dialogue that links our current ideas with those of the past and what may be the most promising new directions of philosophy in the future. In my view --just as those who practice philosophy as part of academies and institutions need to appreciate the value of philosophy done by those who are not part of official academies, it is good for those seeking to practice philosophy independently to explore the resources of academic communities ---perhaps the most healthy was to love wisdom the literal meaning of the term 'philosophy' is to be open to the wisdom one might find both in and outside the academies of our time.

## Can studying philosophy help one to become more creative? What percent of the

Can studying philosophy help one to become more creative? What percent of the first year undergrads you've taught have had original thoughts in their heads at any time?

Yes. And 100%.

OK, perhaps those answers are too short and uncreative.

But yes, I think reading philosophy, thinking about philosophical questions, and trying to come up with and write about philosophical issues can stimulate creative thinking and improve one's creativity (perhaps not artistic creativity but new ways of thinking about things, new ideas, etc.). I think philosophy students tend to become better at imagining different options and solutions and at writing new types of arguments. I'm allowing my current senior major students to do a creative project to engage with the topic we're discussing (death and the meaning of life), and we'll see what they come up with, but music, drama/dialogues, short films, and video games are possibilities.

And it's 100% because original thoughts happen all the time. Each one of us experiences things in ways no one else has. If you meant original answers to philosophical questions, well, then it's probably much lower, but those are not so easy to come up with.