I once read that "moral properties are causally inert". In other words, the fact that something is morally good or right doesn't make anything (or at least anything physical) happen or cease to happen. Only the fact that somebody BELIEVES that something is good or right does. My question is whether you think that this is specific to moral properties. For instance, aesthetical properties (like beauty) seem to be as inert as moral ones. And the properties of being money, of winning a game or of having an A as a school grade seem to me equally inert. Aren't they?

Logic textbooks which offer a system of natural deduction containing a so called "rule of replacement" restrict this rule to logically equivalent formulae. Only these can replace each other wherever they occur. I have often wondered why this is so. It seems to me that, having e.g. p q and p&r as lines in a proof (as premisses, say), would allow one to soundly infer q&r directly from them by replacement of p by q in p&r, without requiring that p and r be logically equivalent. In less formal situations, for example, when solving a math problem, I find myself (and others) doing this all the time. I've searched the internet for this, but couldn't find any answer so far. Most grateful in advance for a reply.

Omnivores are often defined as opportunistic feeders, in other words; they eat what they can get their hands on. As vegetarian sources of food are generally plentiful in the developed world; are there any valid reasons for eating meat? I’m finding it extremely difficult to think of any rational reasons for eating meat in my own life since I’m entirely able to survive on vegetarian options whilst still getting the nutrients I require. The strongest ‘weak’ argument I’ve came up with is it is ‘natural’ for us to eat meat – our bodies are able, and ready, to digest it. Like I said; this argument doesn’t win me over; there are many ‘natural’ things in this world that aren’t necessary for one to live a good life (and many more to contradict living one). For example; cancer is entirely natural – it is observed in the natural world. Likewise; the process of rape as a means of propagating has been observed in the animal kingdom (i.e. in chimpanzees and even dolphins), but I would never use the ‘natural’ argument...

No art exists but what man calls art, and man is partial. If this is true, and if it means that art is only valuable to men, and is thus immaterial outside of that context (the Human Context), then what is the true value of art-—the objective value? I would presume that it is valueless. Further, if an artist knows this, how can he still appreciate art, knowing it to be esoterically meaningful? …*Why* should he continue to appreciate art? --Darwin K.

Look at this inference: Premise 1: All desks have the same color. Premise 2: That desk is brown. Conclusion: All desks are brown. Now, I understand that this is a deduction. However, the conclusion is a generalization of one of the premises, and generalizations of premises are what one would expect in induction. Where did I go wrong?

Would Immanuel Kant oppose alternative rock? If we were to universalize the maxim "It is permissible to listen to alternative rock" then "alternative" rock would become mainstream, since everyone would listen to it. This of course creates a contradiction, implying we have a perfect duty not to listen to alternative rock. (I'm not trying to be silly. I think I've wildly misinterpreted Kant, and I was wondering if you could clear it up.) You might say that just because alt. rock was permitted, that doesn't mean everyone would listen to it. But if stealing was permitted, it doesn't logically follow that everyone would steal. (Same goes for lying.)

During discussions with one of my friends (who is an undergraduate biologist) we often enter into the empiricism vs. rationalism debate. In support of empiricism as the best route to true knowledge my friend often cites the many practical achievements made throughout history resulting from a scientific/empirical approach. In response to this I find it difficult to cite any significant advancements or examples of knowledge which can be credited to the side of rationalism. Indeed it seems to me the invocation of science's great 'utility' is often used as a defence of its (sometimes questionable) actions as well as its assumed superiority as a means to true knowledge. Therefore my question is how can one most effectively challenge science's monopoly on truth and knowledge (particularly in today's 'science worshipping society') in the face of its great practical achievements?

Many great thinkers are pessimists and often reach the conclusion that everything is pointless. Tolstoy even said that life is just a "sick joke". I started to read a lot of philosophy and I reach the same conclusion, that there is no absolute meaning and life is pretty pointless. And please don't reply that we should live in the now or we make our own happiness, etc.

I have a daughter that is 14 years young. As a mother I understand that teenagers in her age grow up and they want to have fun, most of them with the guys. But still I can't let her go out. I think it's wrong. But my question is, Is that really wrong? Because I remember myself in her age... I also see the friends around her, they don't go out... well she's the only one. But she suffers because of me not letting her to have a boy-friend. Do you think I should let her? Because I'm really confused...

Is consciousness a byproduct or “add-on” of our evolution or is it something that is intrinsic and inseparable from the skills we humans have? I know this question sounds strange but it's something that has bugged me for quite some time.