Ever since the Supreme Court issued its astoundingly bad decision in Kelo v. City of New London, local governments have been encouraged to use eminent domain schemes to grab private property for the commercial benefit of their well-connected cronies -- all in the name of public welfare. The schemes are getting more sophisticated now. An enterprising company called Mortgage Resolution LLC has put together a package that's tempting a number of municipalities, especially in the law-free zone known as California, though nibbles of interest are coming in from Seattle and Newark as well. The gambit is to identify home mortgages that are underwater but current on their payments. Mortgage Resolution LLC puts together a local package of these mortgages whose borrowers pass a credit test, then persuades the local government to "condemn" the mortgages at a price equal to 80% of the home's fair market value. The lenders (typically owners of mortgage-backed securities pools) take a hit equal to the excess of the mortgage balance over the home's value, plus 20% of the home's value. Mortgage Resolution LLC then refinances the homes through the FHA and pays the local government a percentage of its profits. It's like a tax on highway robbery: the more we rob, the more the city collects in taxes! And the people we rob mostly live out of state, anyway, so who cares?
Boston law firm Ropes & Gray has filed a lawsuit challenging the scheme on constitutional grounds. At issue is the horrendously confused law of eminent domain and "public use" in the wake of the Kelo decision. That case left open the possibility of relief for eminent domain schemes in which the seizure of property was a mere "pretext" rather than a good-faith pursuit of the public welfare. Later courts, however, have struggled to develop a workable definition of "pretext."
The Kelo decision spurred action in many state legislatures to curb the power of local government to grab any property they thought might be convenient for the visionary real estate development schemes of their cronies. These legal fixes evidently hadn't much teeth in California, Washington, or New Jersey. In any event, the idea of grabbing and reselling mortgages rather than homes is a fresh and exciting abuse that offers up the possibility of ensuring that the loss lands on faceless profit-grubbing lenders instead of photogenic local homeowners. It still amounts to theft, however, and in the long run it won't help homeowners ensure access to a reasonable mortgage market.
Tactical!
Reader AW from LuckyGunner sends the following ad for Blackhawk Tactical goggles, which has an amusing video showing the many 'tactical' day to day uses to which you might put them. I think he likes one of them particularly because he is expecting a baby in just a few months!
The day-to-day-tactical is played for laughs, but as I was telling him by email, I actually do wear my old tactical goggles on the motorcycle. They were designed to protect the eyes and face from IED shrapnel, so they're good to go for most of the stuff that you might encounter on the highway. As the ad says, "These goggles offer great wind and dust protection thanks to their foam dust filters in the ventilation system." That's just what a biker needs, too.
Of course, like everything designed for the tactical market, "tactical" goggles do cost more than regular biker goggles. But the protection level is higher, and the eyes are worth protecting.
The day-to-day-tactical is played for laughs, but as I was telling him by email, I actually do wear my old tactical goggles on the motorcycle. They were designed to protect the eyes and face from IED shrapnel, so they're good to go for most of the stuff that you might encounter on the highway. As the ad says, "These goggles offer great wind and dust protection thanks to their foam dust filters in the ventilation system." That's just what a biker needs, too.
Of course, like everything designed for the tactical market, "tactical" goggles do cost more than regular biker goggles. But the protection level is higher, and the eyes are worth protecting.
Historical Fiction as Thesis
I'm not sure where the affection for the Cathar heresy comes from, but I can't remember the last time I saw an academic paper that didn't treat it as some sort of wrongly-suppressed, righteous and wonderful movement. If only our ancestors had embraced its complete rejection of reproduction!
This one goes so far as to construct a "historical thesis" that is really a piece of imaginative narrative fiction. If one can get a Master's degree for writing historical fiction, Lars Walker should have a Ph.D.
This one goes so far as to construct a "historical thesis" that is really a piece of imaginative narrative fiction. If one can get a Master's degree for writing historical fiction, Lars Walker should have a Ph.D.
Weddings back in style
The U.S. military has been struggling with its policy on dependent benefits. On the one hand, any large, complex organization would like to have a simple rule for who qualifies as a dependent, so it can exert some predictable control over a very large fraction of the cost of its wage packages. The easiest rule, by far, is to let the bright line of marriage define the family. On the other hand, the trend also has been to avoid discriminating against gay partners, and requiring marriage is a cruel trick to play if marriage isn't available.
Now that the Supreme Court has ruled that gay marriages must be acknowledged, the military evidently is reverting to the assumption that people who want coverage for their partners had better go ahead and marry them. It's going to be interesting to see how this trend plays out against the countervailing trend, which is against letting the Man make rules about who's a family and who's not. Can common-law gay marriages be far away? Will there be shotgun marriages for gays who want to adopt?
Now that the Supreme Court has ruled that gay marriages must be acknowledged, the military evidently is reverting to the assumption that people who want coverage for their partners had better go ahead and marry them. It's going to be interesting to see how this trend plays out against the countervailing trend, which is against letting the Man make rules about who's a family and who's not. Can common-law gay marriages be far away? Will there be shotgun marriages for gays who want to adopt?
Beautiful Crusader Hospital Found in Jerusalem
The pictures are lovely. One of the sorrows of the war in Syria is watching old and beautiful sites like Krak des Chevaliers being damaged by the war. Of course they were made for war, and the region is long troubled.
But how nice that, in Jerusalem, there is enough peace that this site can instead be renovated for happier purposes:
But how nice that, in Jerusalem, there is enough peace that this site can instead be renovated for happier purposes:
Monser Shwieki, the project manager, explained “The magnificent building will be integrated in a restaurant slated to be constructed there, and its patrons will be impressed by the enchanting atmosphere of the Middle Ages that prevails there”.I expect it will be a very pleasant place.
How To Raise a Daughter: Two Parallel Views
A lady I know, for whom I have the greatest respect though we often do not agree, sends this video with an approving comment. "My kind of girl!"
The lady in question did raise a daughter, actually, and I'm quite sure she wouldn't have accepted such an attitude from her own daughter. But she wants to indicate that she approves of female self-assertiveness, I suppose.
I have a hard time not viewing this as a kind of child abuse. The child is at an age when she is learning how to treat others, and whether she learns to treat her elders with respect or with a kind of royal disdain is really going to be a question of the sort of feedback she receives. The family has her in a kind of isolation, so that the feedback she gets will initially be contained to what they elect to give her. If they giggle and laugh approvingly at her imperious dictates, she won't be wrong in committing to those habits as demonstrably successful.
When she gets out in the world, however... well.
Naturally I thought of this article from the NYT's parenting section, which I'm sure we all read last week. That child did not learn to spew hate tinged with explicit sexual terminology at the age of ten on her own.
Fate has not given me a daughter, so I can't say how I would raise one with certainty. It's a very difficult problem. I honor those, like my late father-and-mother-in-law, who managed it with grace.
The lady in question did raise a daughter, actually, and I'm quite sure she wouldn't have accepted such an attitude from her own daughter. But she wants to indicate that she approves of female self-assertiveness, I suppose.
I have a hard time not viewing this as a kind of child abuse. The child is at an age when she is learning how to treat others, and whether she learns to treat her elders with respect or with a kind of royal disdain is really going to be a question of the sort of feedback she receives. The family has her in a kind of isolation, so that the feedback she gets will initially be contained to what they elect to give her. If they giggle and laugh approvingly at her imperious dictates, she won't be wrong in committing to those habits as demonstrably successful.
When she gets out in the world, however... well.
Naturally I thought of this article from the NYT's parenting section, which I'm sure we all read last week. That child did not learn to spew hate tinged with explicit sexual terminology at the age of ten on her own.
Fate has not given me a daughter, so I can't say how I would raise one with certainty. It's a very difficult problem. I honor those, like my late father-and-mother-in-law, who managed it with grace.
Social Harmony, Illustrated
A post of enduring popularity has been "Social Harmony," from way back in 2004.
I was reading an article the other day, in the local newspaper, about an elderly Korean gentleman who has moved into town and opened a martial arts studio. He chastened the reporter who had come to interview him not to suggest that the martial arts were 'all about fighting.' "No!" he said. "The purpose is social harmony."It's always nice to encounter a strong example that illustrates your point.
That is exactly right. The secret of social harmony is simple: Old men must be dangerous.
Formal Logic, Part III
Today I'm going to depart from the textbook for a moment, and work out some consequences of what you've seen in the first two parts. There's something very significant lurking here, and students of logic usually pass over it without forcing it out into the light.
In the last part we worked on the concept of logical equivalence, which is when two forms of an argument have exactly the same truth values in every case. This has an important consequence: because the two forms preserve each other's truth, you can substitute one for the other. Just as in mathematics, you can treat equalities as interchangable. If it is helpful in getting where you need to go in algebra, for example, you can divide both sides of an equation by two, or multiply them both by two. The truth of the equation is preserved:
ab=2
2(ab)=4
0.5(ab)=1
Likewise:
J ≡ M
M ≡ J
Once we get past the foundations of formal logic, and into advanced logic, this mathematical assumption becomes more and more important. Logical deductive systems have strict rules governing substitutions that are supposed to be truth-preserving. Various operators have different rules, so it is often important to be able to substitute one set of operators for another in order to reach the final result you are seeking.
Here is an example. In modal logic, the following two propositions are thought to be readily exchangable:
◊p ("Possibly p," or proposition p is possible)
~□~p ("Not-necessarily-not p," or, p is not necessarily forbidden -- and is, therefore, possible)
You can do the same thing with "necessarily P" and "not-possibly-not p."
Why does that matter? One reason is that there are rules for handling the box of necessity (□) that differ from the not-operator (~). You can only derive possibility from possibility (◊), but if you can switch to the not-necessarily-not and eliminate the first "not," you can then derive a necessary truth using the box forms.
Because all of these forms are thought to be proven to preserve truth, this means that you can use these advanced logical forms to move from a proposition known to be true to another very different proposition that you can treat as necessarily true also.
This is why, for more than a hundred years, this kind of logical philosophy has had pride of place in the Anglo-American world. It believes it is bringing something very much like mathematical precision to the wider world of human knowledge. If you also believe that, it is a very exciting field even today.
Nothing like this is true for Aristotle's philosophy. That is not to say that he didn't see a relationship between the mathematics of his day, and the logic of his day. He also saw a relationship between the logic of his day and the practical human problems of his day. However, he explicitly rejected the idea that you could create a deductive logic that applies directly to practical human problems. As he says in Nicomachean Ethics I.3:
However, there are counterexamples. The poet Sydney Lanier, during his time as a Confederate officer aiding British blockade runners as a pilot, behaved courageously and honestly in refusing to disguise himself as British when overhauled by a Union naval vessel. As a result, he caught tuberculosis while interned as a prisoner of war and died before he was forty. His virtues caused him to produce some remarkable works of literature and music, but they also killed him.
Now a proper defense of contemporary logic might suggest that they have an out here. Truth-preserving forms can only preserve as much truth as was in the original proposition. Thus, if the original proposition you are starting from is -- as Aristotle says -- not necessarily true but only probably true, your conclusion can only be taken to be probably true as well.
But I think Aristotle's point is stronger than that. He's very much in favor of applying "a sort of syllogism" to the problems of everyday life, but he's also clear that there is a kind of double analogy at work. First of all, the earlier practical problem you are taking as an example is an analogy, and analogies are always a little imprecise. If we say "our current situation is like Washington at Valley Forge," we don't really mean that it's exactly like Washington's situation. There's an imprecision.
In addition, the kind of logic we can apply to these analogies isn't going to offer us truth-preservation in the same way as what Aristotle calls "strict logic." It's going to be a "sort of syllogism" we can actually bring to bear, and for a good reason: even if we should go as far as translating our problems into the mathematical language of formal logic, so we can apply a strict deduction according to rigorous forms, we will have introduced new ambiguities in the translation. That is, of course, just why Bertrand Russell and others preferred to symbolize propositions: they hoped to eliminate ambiguities of natural language. Finally, it simply cannot be done: strict logic doesn't admit of many of the elements we need to capture all the details of a real-world problem.
(A great example of this is the symbolized forms of St. Anslem's Ontological Proof for the Existence of God. It's a valid argument when symbolized... but it can't actually prove what Anslem was after, because it is necessary to formalize "best" or "better than" in a way that loses his sense of the term entirely.)
In any case, this is a major difference between the ancient and medieval understanding of logic, and the contemporary form. Whether you view the contemporary enchantment with mathematical logic a romance or a seduction depends on your view of the character of the logic itself. I believe Aristotle still has the best of this argument, even though he never got to see the development of algebra, or the subsequent similar refinements in formal logic.
In the last part we worked on the concept of logical equivalence, which is when two forms of an argument have exactly the same truth values in every case. This has an important consequence: because the two forms preserve each other's truth, you can substitute one for the other. Just as in mathematics, you can treat equalities as interchangable. If it is helpful in getting where you need to go in algebra, for example, you can divide both sides of an equation by two, or multiply them both by two. The truth of the equation is preserved:
ab=2
2(ab)=4
0.5(ab)=1
Likewise:
J ≡ M
M ≡ J
Once we get past the foundations of formal logic, and into advanced logic, this mathematical assumption becomes more and more important. Logical deductive systems have strict rules governing substitutions that are supposed to be truth-preserving. Various operators have different rules, so it is often important to be able to substitute one set of operators for another in order to reach the final result you are seeking.
Here is an example. In modal logic, the following two propositions are thought to be readily exchangable:
◊p ("Possibly p," or proposition p is possible)
~□~p ("Not-necessarily-not p," or, p is not necessarily forbidden -- and is, therefore, possible)
You can do the same thing with "necessarily P" and "not-possibly-not p."
Why does that matter? One reason is that there are rules for handling the box of necessity (□) that differ from the not-operator (~). You can only derive possibility from possibility (◊), but if you can switch to the not-necessarily-not and eliminate the first "not," you can then derive a necessary truth using the box forms.
Because all of these forms are thought to be proven to preserve truth, this means that you can use these advanced logical forms to move from a proposition known to be true to another very different proposition that you can treat as necessarily true also.
This is why, for more than a hundred years, this kind of logical philosophy has had pride of place in the Anglo-American world. It believes it is bringing something very much like mathematical precision to the wider world of human knowledge. If you also believe that, it is a very exciting field even today.
Nothing like this is true for Aristotle's philosophy. That is not to say that he didn't see a relationship between the mathematics of his day, and the logic of his day. He also saw a relationship between the logic of his day and the practical human problems of his day. However, he explicitly rejected the idea that you could create a deductive logic that applies directly to practical human problems. As he says in Nicomachean Ethics I.3:
Our discussion will be adequate if it has as much clearness as the subject-matter admits of, for precision is not to be sought for alike in all discussions, any more than in all the products of the crafts. Now fine and just actions, which political science investigates, admit of much variety and fluctuation of opinion, so that they may be thought to exist only by convention, and not by nature. And goods also give rise to a similar fluctuation because they bring harm to many people; for before now men have been undone by reason of their wealth, and others by reason of their courage. We must be content, then, in speaking of such subjects and with such premisses to indicate the truth roughly and in outline, and in speaking about things which are only for the most part true and with premisses of the same kind to reach conclusions that are no better. In the same spirit, therefore, should each type of statement be received; for it is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject admits; it is evidently equally foolish to accept probable reasoning from a mathematician and to demand from a rhetorician scientific proofs.Likewise in the Rhetoric I.1:
Persuasion is clearly a sort of demonstration, since we are most fully persuaded when we consider a thing to have been demonstrated. The orator's demonstration is an enthymeme, and this is, in general, the most effective of the modes of persuasion. The enthymeme is a sort of syllogism, and the consideration of syllogisms of all kinds, without distinction, is the business of dialectic, either of dialectic as a whole or of one of its branches. It follows plainly, therefore, that he who is best able to see how and from what elements a syllogism is produced will also be best skilled in the enthymeme, when he has further learnt what its subject-matter is and in what respects it differs from the syllogism of strict logic. The true and the approximately true are apprehended by the same faculty; it may also be noted that men have a sufficient natural instinct for what is true, and usually do arrive at the truth. Hence the man who makes a good guess at truth is likely to make a good guess at probabilities.Aristotle preserves the idea that strict logic is closely related to practical decision-making, which is the proper subject matter of rhetoric and ethics and political science. But he explicitly rejects the idea that you can obtain a deduction, a demonstration, of the sort that contemporary analytic philosophy often seeks. His examples are on point: in general, courage is a praiseworthy quality, and most of the time it will lead you to greater success in life.
However, there are counterexamples. The poet Sydney Lanier, during his time as a Confederate officer aiding British blockade runners as a pilot, behaved courageously and honestly in refusing to disguise himself as British when overhauled by a Union naval vessel. As a result, he caught tuberculosis while interned as a prisoner of war and died before he was forty. His virtues caused him to produce some remarkable works of literature and music, but they also killed him.
Now a proper defense of contemporary logic might suggest that they have an out here. Truth-preserving forms can only preserve as much truth as was in the original proposition. Thus, if the original proposition you are starting from is -- as Aristotle says -- not necessarily true but only probably true, your conclusion can only be taken to be probably true as well.
But I think Aristotle's point is stronger than that. He's very much in favor of applying "a sort of syllogism" to the problems of everyday life, but he's also clear that there is a kind of double analogy at work. First of all, the earlier practical problem you are taking as an example is an analogy, and analogies are always a little imprecise. If we say "our current situation is like Washington at Valley Forge," we don't really mean that it's exactly like Washington's situation. There's an imprecision.
In addition, the kind of logic we can apply to these analogies isn't going to offer us truth-preservation in the same way as what Aristotle calls "strict logic." It's going to be a "sort of syllogism" we can actually bring to bear, and for a good reason: even if we should go as far as translating our problems into the mathematical language of formal logic, so we can apply a strict deduction according to rigorous forms, we will have introduced new ambiguities in the translation. That is, of course, just why Bertrand Russell and others preferred to symbolize propositions: they hoped to eliminate ambiguities of natural language. Finally, it simply cannot be done: strict logic doesn't admit of many of the elements we need to capture all the details of a real-world problem.
(A great example of this is the symbolized forms of St. Anslem's Ontological Proof for the Existence of God. It's a valid argument when symbolized... but it can't actually prove what Anslem was after, because it is necessary to formalize "best" or "better than" in a way that loses his sense of the term entirely.)
In any case, this is a major difference between the ancient and medieval understanding of logic, and the contemporary form. Whether you view the contemporary enchantment with mathematical logic a romance or a seduction depends on your view of the character of the logic itself. I believe Aristotle still has the best of this argument, even though he never got to see the development of algebra, or the subsequent similar refinements in formal logic.
Faction
At RealClearPolicy, James v. Delong writes about one of the dangers of letting government get too big: it becomes even more difficult to moderate the natural tendency of factions to use the democratic process to vote themselves public goodies.
Capture by faction has become endemic. As government has grown and budgets and regulatory empires have expanded, economic and ideological factions have carved off satrapies in the agencies and congressional subcommittees. The true greens control EPA. Unions have Labor and the NLRB. The banks have the Fed and Treasury. The energy companies used to have the Department of Energy, but now it is in the hands of the green crony capitalists. Farm policy is controlled by a coalition of agricultural interests and food-stamp advocates. HUD serves housing industry and urban constituencies. HHS and its state satellites are a tool of the health-care industry -- my state senator in Montana deals with 63 health-care lobbyists, all of them focused on one thing: more money from the state. Academia, teachers' unions, and the consulting industry control the Department of Education. Public employees have become a powerful interest group in themselves. And so on.
Conservatives keep arguing about Obama's political philosophy, but they miss the point. His strength is that he has none. He has no views on environmental or labor or health or education policy; whatever the interests that have been given that part of the government want is all right with him. His job is to assure each member of his coalition that it will indeed be given freedom of action, to mediate the occasional conflicts, and to serve as a mouthpiece when interest-group talking points are put on his teleprompter.* * *
The rise of this special-interest state was not totally without a justifying political theory. It was accompanied by a school of analysis called "interest-group liberalism," which posited that the various interest groups elbowing each other on the way to the trough would produce in the political system the self-regulating efficiencies that free-market competition produces in the economic sphere. This was always just a metaphor, not a real analysis, and it does not stand up as a serious philosophy.It's that last part that most interests me. Competition in the form of a race for the spoils doesn't work. Competition can work to increase overall prosperity if it rewards productive behavior, but scrambling for political favors doesn't reward productive behavior. It's more like announcing a police holiday and encouraging everyone to loot. The kind of competition we need is the kind that spurs people to offer something more valuable so that other free people will willingly enter into a trade with them, even though they have alternatives. In theory, you might use a democratic voting process to mediate those sorts of trades, but in practice it's far too clumsy. It can't use price signals as effectively as the fine-grained system that leaves ever producer and consumer free to bargain with equals. The spoils that each interest faction scramble for don't belong to the people who award them, so the price signals are all broken and the supply and demand can't be brought into balance.
Whose Purpose Is To Kindle
Today's sending-forth hymn omitted one of its three verses. It is sung to the Ode to Joy.
God, who still a sword delivers rather than a placid peace,
with your sharpened sword disturb us, from complacency release!
Save us now from satisfaction, when we privately are free,
yet are undisturbed in spirit by our neighbor’s misery.
Secrets and low-hanging fruit
An interesting article, by way of Assistant Village Idiot's sidebar, about ideas that already have been discovered, but never publicized.
Formal Logic, Part II
Part I is here, along with the text we're using. We'll begin today with Section 1.10, because I want to talk about logical equivalence.
Last time we talked about validity, and the difference between Aristotle's ideas of validity and modern ones. But there's another way of talking about validity in logic, which is this: an argument can be said to be valid if it is truth-preserving. That doesn't mean that it guarantees truth (see the section on "soundness"), but that a valid form will preserve whatever truth is there. If your propositions are true, a valid form will ensure that your conclusion is also true.
Truth-preservation is also why we can say that two apparently very different arguments are logically equivalent. What it means for two arguments to be logically equivalent is that the two arguments are true or false together, 100% of the time. If you go through the exercises of building truth tables, you'll see that the truth tables for the two arguments will be exactly, precisely the same in every case.
Consider one of his examples:
1) Either it is raining, or it is snowing but not raining.
2) Either it is raining or it is snowing.
Since this is the inclusive "or," if it is both raining and snowing both of these sentences are considered true (because the "either it is raining" part is true). Symbolically, (1) would be rendered (R v (S & ~R)), and (2) would be (R v S). If the "R" is satisfied, the sentence is true; if the S is satisfied, both sentences are true if it is not raining. Both sentences are false if it is neither raining nor snowing.
There's a shorthand way of saying that two logical sentences are equivalent, which is called the biconditional. It is rendered in natural language "if and only if," or in philosophical shortcut, "iff." It has several logical symbols, but where I come from we use the triple bar: ≡.
Note, though, that this kind of equivalence goes both ways. 1≡2 means 2≡1. That is not the case for every sort of sentence we would render in natural language with "only if." "He is a bachelor if and only if he is an unmarried male human" is a biconditional (as well, in this case, as a tautology) because wherever one set of things will be true, the other will, and vice versa.
The other kind of 'only if' is a material conditional. You could say "If John gets hired, then Mary will get hired." But that does not mean that the truth of John's hiring is equivalent to the truth of Mary's hiring. It means that "John will get hired only if Mary gets hired."
That's properly:
3) J -> M
Not:
4) J ≡ M
We can see they are not equivalent by building the truth table.
J M | (3) | (4)
---------------
T T | T | T
T F | F | F
F T | T | F
F F | T | T
Because the truth values of the claims do not hold together, the material conditional form of the statement is not logically equivalent to the biconditional. And while (J ≡ M) is the same as (M ≡ J), (J -> M) is not the same as (M -> J). The table for (M -> J) I will leave you to work out on your own as an exercise, if you choose, but you will see it comes apart from (J -> M).
Preserving the truth is what this is all about.
Last time we talked about validity, and the difference between Aristotle's ideas of validity and modern ones. But there's another way of talking about validity in logic, which is this: an argument can be said to be valid if it is truth-preserving. That doesn't mean that it guarantees truth (see the section on "soundness"), but that a valid form will preserve whatever truth is there. If your propositions are true, a valid form will ensure that your conclusion is also true.
Truth-preservation is also why we can say that two apparently very different arguments are logically equivalent. What it means for two arguments to be logically equivalent is that the two arguments are true or false together, 100% of the time. If you go through the exercises of building truth tables, you'll see that the truth tables for the two arguments will be exactly, precisely the same in every case.
Consider one of his examples:
1) Either it is raining, or it is snowing but not raining.
2) Either it is raining or it is snowing.
Since this is the inclusive "or," if it is both raining and snowing both of these sentences are considered true (because the "either it is raining" part is true). Symbolically, (1) would be rendered (R v (S & ~R)), and (2) would be (R v S). If the "R" is satisfied, the sentence is true; if the S is satisfied, both sentences are true if it is not raining. Both sentences are false if it is neither raining nor snowing.
There's a shorthand way of saying that two logical sentences are equivalent, which is called the biconditional. It is rendered in natural language "if and only if," or in philosophical shortcut, "iff." It has several logical symbols, but where I come from we use the triple bar: ≡.
Note, though, that this kind of equivalence goes both ways. 1≡2 means 2≡1. That is not the case for every sort of sentence we would render in natural language with "only if." "He is a bachelor if and only if he is an unmarried male human" is a biconditional (as well, in this case, as a tautology) because wherever one set of things will be true, the other will, and vice versa.
The other kind of 'only if' is a material conditional. You could say "If John gets hired, then Mary will get hired." But that does not mean that the truth of John's hiring is equivalent to the truth of Mary's hiring. It means that "John will get hired only if Mary gets hired."
That's properly:
3) J -> M
Not:
4) J ≡ M
We can see they are not equivalent by building the truth table.
J M | (3) | (4)
---------------
T T | T | T
T F | F | F
F T | T | F
F F | T | T
Because the truth values of the claims do not hold together, the material conditional form of the statement is not logically equivalent to the biconditional. And while (J ≡ M) is the same as (M ≡ J), (J -> M) is not the same as (M -> J). The table for (M -> J) I will leave you to work out on your own as an exercise, if you choose, but you will see it comes apart from (J -> M).
Preserving the truth is what this is all about.
Snakebit
September 11, 2001, was a really bad day to get a lethal snakebite in Myanmar and need an air evacuation. Now there's a new first-aid treatment for neurotoxin-type snake venom that was inspired in part by one unfortunate scientist's experience. The treatment doesn't break down the venom directly, but it helps you live with it a bit longer while you get to a hospital or your body breaks down the venom naturally:
Most neurotoxins work by attacking the neuromuscular junction – the regions between the nerves and the muscles that trigger the muscles to move when the brain signals them. They do this by blocking an essential neurotransmitter – acetylcholine – from passing from the nerve to the muscle, telling it to move. The result is paralysis, even in the crucial lung muscles. . . .
A patient in this predicament needs antivenom, a molecule that deactivates the venom directly. Neostigmine cannot do this, but can allow what little acetylcholine is able to get past the venom to move freely. And in an emergency, you need every second.Rattlesnake vaccine is good, too, though it's available only for dogs and horses, not people. It's not expensive, and most of the time it converts a real medical nightmare into a minor inconvenience.
What we know
From Maggie's Farm, this Reason article about seven common misperceptions, including the idea that markets make people mean (or poor).
"15 Minutes Prior"
Boy does this seem familiar.
H/t Mr. Sparkle, who introduced me to one of the British military humor sites.
H/t Mr. Sparkle, who introduced me to one of the British military humor sites.
...And Shove It
Taranto reports that a Tennessee news editor lost his job over a headline borrowed from an old Johnny Paycheck song.
Don't feel bad. Authority figures of a certain cut have always found that song offensive to their heightened sense of dignity.
Don't feel bad. Authority figures of a certain cut have always found that song offensive to their heightened sense of dignity.
Good News!
The Executive branch has graciously granted Congress a waiver from Obamacare. There was some real concern there that the people who passed this law might have to abide by it.
Or, as the first comment says, "Whew! You don't know what a relief it is, knowing our rulers won't have to pay some of their own personal expenses."
Or, as the first comment says, "Whew! You don't know what a relief it is, knowing our rulers won't have to pay some of their own personal expenses."
Some Help on NSA Programs
The MSM occasionally still produces helpful journalism. Here are two pieces on the NSA question that are useful in following the issue.
First, General Alexander speaks to the Black Hat hacker conference. This is what the best defense of NSA looks like, constructed for a conference of people whom the NSA knows will see through any obfuscations. So this is the upside.
Second, an analysis of similar testimony presented to Congress. This is part of what the downside looks like.
First, General Alexander speaks to the Black Hat hacker conference. This is what the best defense of NSA looks like, constructed for a conference of people whom the NSA knows will see through any obfuscations. So this is the upside.
Second, an analysis of similar testimony presented to Congress. This is part of what the downside looks like.
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