what do you know that you do not know?

This question can be interpreted in at least two different ways, based on internal ambiguities. From one perspective, we can take it as a inquiry about those things we have knowledge of our own lack of knowledge about. I know that I do not know what day I will die, or what the afterlife might be like. I know that I do not know if there are aliens in outer space. I know that I do not know how to speak the Zulu language.

On the other hand, we can take the “that” as an equals sign, and the question becomes the paradoxical one, what is it that you both know and do not know (simultaneously). It is an easy temptation to dismiss questions like this out of hand, as meaningless nonsense, but as powerful thinkers from Ecclesiastes to Kierkegaard to Nils Bohr and beyond have noted, it is the most paradoxical concepts that tend to lead to the most powerful insights.

Unfortunately, in this case, no powerful insight arises for me –at least not immediately –out of contemplating this question, so for the moment, I will simply leave it with this respectfully inadequate answer.

On one hand, arguments are supposed to be objective – something which is true is always true, for everyone. On the other hand, if person says “P exists because X,Y,Z”, while he personally has seen the evidence (x,y,z) for P, and another person says “P exists because X,Y,Z” and he has only read about X,Y,Z from second sources – their knowledge is actually very different. Where is that difference (crucial one) reflected in logic?

I think your question is rooted in the fact that we generally consider two distinguishably different subjects under the umbrella of logic. The first is the art of argument as it takes place in natural language. The second is an deliberately constructed system, first proposed by Aristotle, and later greatly extended and expanded by figures such as Boole and Frege, which is intended to capture some of the essential qualities of natural argument, but to do so in a way that has mathematical rigor, precision and surety.

In ordinary language some of the arguments we use are based on matters of fact, the perceived truth of which cannot help but be subjective. Other arguments are largely definitional and thus deductive –they express relations of ideas that follow directly and inevitably from agreed-upon definitions.

In formal logic, the only arguments allowed are of the second type, and they exist within a framework carefully constructed so as to eliminate all remaining ambiguities of context, meaning and truth value. Thus, they can truthfully be described as objective and sure to the same extent and with the same assurance as mathematical truths such as “2+2=4” –at least (and this is an important caveat!) within the agreed-upon framework.

Your example of [(x AND y AND z ) IMPLY p ], however, shows the effects of mixing the two types of argument in ordinary language. Let us assume that there is a valid deductive relationship between x,y and z and p. In that case, given x,y, and z, it would be objectively the case that p would also have to be true. But all arguments are essentially hypothetical statements. The conclusion is only as good as the premises. If we have reason to doubt x,y and z, then we have equal reason to doubt p (assume we have no independent reason to believe p).

In general, deductive arguments are “objective”, inductive arguments are “subjective.” But one should be aware of an additional opportunity for confusion stemming from the concept of “mathematical induction,” which, despite its name, is an objective and sure process for establishing mathematic truths. This concept encompasses all arguments of the form “f(0), f(n) IMPLIES f(n+1), therefore all f”. It is so-named because of superficial similarities to ordinary language induction, but it gains a rigor on its way into mathematics that moves it into the realm of surety.

I would take a standard textbook on math, where all the propositions are correct. Write down 99 correct mathematical statements. And then add “Zeus exists”, and compile a text. Then I would argue, that if we have a box, from which we sample randomly 99 balls and they are have the property of being black, we can think with good reason that the next one will be black. And therefore, since 99 of the math propositions in the texts are have the property of being correct, there is good reason to think that “Zeus exists” is also correct. It seems wrong somewhere. But where?

No matter how strong an inductive argument is, it cannot guarantee results the same way a deductive argument can. It is always theoretically possible for the premises of an inductive argument to be true and the conclusion to be false.

In the case you mention, one might make a strong inductive argument to the effect that since the first 99 statements in the book were true, the last would be as well –but that conclusion might still be false. Furthermore, if you are aware of how the book was constructed and you do not include that information in your argument, you are guilty of the fallacy of suppressed evidence, and the argument can no longer be considered “strong.” Clearly, writing a false statement in a book of all true statements does not magically make that last statement true, and your knowledge of that fact must therefore be counted as a factor when judging the strength of the argument.

That may seem hopelessly subjective, but unlike the mathematically precise and assured conclusions of deductive arguments, the conclusions of inductive arguments can never be divorced from the real-world vagaries of context and circumstance.

Is Lucifer interpreted as pining for the God he once loved and has been cast down by” sorry more of a theological question here (agnostic’s novel research)

Thanks for your question. One important thing to remember here is that with a few brief exceptions, the devil is barely mentioned in the Bible itself –and in fact, the one mention of “Lucifer” by name may not even refer to the devil at all. So from that point of view, there isn’t really an “official” answer to your question. The majority of the lore about Lucifer in the Western tradition comes from Dante’s Inferno and Milton’s Paradise Lost, so if you want to be in tune with the general opinion, those would be the sources to check. Generally the understanding is that Lucifer was the best and brightest of the angels, until he tried to arrogate God’s place as ruler of the universe.

None of this answers your question, but given Lucifer’s extra-canonical nature, I think you’d be perfectly justified in exploring your own interpretation. You might also find it interesting to note that in the Islamic tradition, the devil is considered a “loyal” but misguided servant of God, whose chief crime is his jealousy and hostility towards mankind, and whose destiny is to be reconciled to God at the end of time.

explain how doubt leads descartes to postulate human essence as non material

I have the unpleasant intuition that someone may be trying to get me to complete their philosophy homework or essay question here. Nonetheless, applying the principle of charity and assuming this query is legitimate, I’ll try to give at least a brief answer:

In general, Descartes’ project is to doubt everything he possibly can, including whether the world exists as we perceive it, or is simply an illusion or deliberately deceiving simulation (as in the movie “The Matrix”). At the end of his process of extreme doubt, all he can be sure of is his famous dictum: “I think, therefore I am”. In other words, he knows he is thinking, because otherwise, he couldn’t even be doubting the things he doubts, and since something must exist in order to think, he knows that he must exist in some form, even if that form is not what he thinks it is. In other words, Descartes might be a space alien, or a creature of pure energy, or a disembodied spirit, or a mathematical abstraction, but he must be something, and that something must be able to think, since he can verify the fact of his thinking by immediate experience.

To put a quick gloss on the situation, this convinces Descartes that what he is in his most essential form is a creature that thinks, since all the material facts about himself could be other than they are without changing the central core of his identity as a thought-capable entity.

Hope that helps you with your test– oops! I mean with your sense of deep philosophical bewilderment. 🙂

whats (if anything) is wrong with epiphenomenalism?

I’ve already answered several questions on this subject, but here’s a quick summary of my view: Epiphenomenalism fails to offer an adequate alternate explanation for the phenomenon it disbelieves –i.e. the subjective experience of making choices and having our bodies respond (at least partially) to our will. In particular, it cannot explain why, given the hypothesis that no part of our bodies is actually under the conscious control of the [fictive?] will, do some parts of the body seem to be under our command, while others, like the heart, do not.

Also, how can one explain the existence of physical skills such as wiggling your ears, playing the piano or juggling? These are highly technical skills that seemingly take willpower to gain. It seems difficult to accept that they are talents our bodies (randomly?) acquire independent of any conscious effort.

A circular argument is technically a valid argument. For every case in which the premises are true, the conclusion will be true. So what makes it a bad one?


Thanks for your question. Although we tend to focus on validity in logic, it is actually only the minimal baseline requirement for a “good” argument. Valid means that the conclusion is guaranteed to be true if the premises are true. But in order for an argument to be “sound” it needs also to have true premises. Otherwise, it might just be “vacuously valid” as in the case where the premises contradict each other, and thus can never be true simultaneously.

P and not P
Therefore X

is also a “valid” argument, no matter what P and X might be. But it can never be sound.
Your case, however is different.

Therefore P

The problem with the circular argument is not that it cannot be sound, but that it does not play the function of an argument –to convince us of things we did not believe before. A circular argument yields exactly and only what you put into it. It does not increase your understanding or store of knowledge. It is “bad” not because it is invalid, but because it is non-functional. If presented in a debate or philosophical paper, it is considered misleading and illegitimate because it claims to prove something that it presents as a given or as an assumption.