Don't many of us regard that "vision" is something like the headlights of a car, casting a beam of light on objects, originating inside the eye? Which is of course completely wrong and the truth is the opposite. Its fairly present in many cultures and even though it is just a mere figure of speech it feels wrong doesn't it?

Do the perceptual systems work from the environment in, or from the perceiver out? In English there are famously two very different groups of perceptual words, one active and one passive: look/see, listen/hear, touch/#feel, smell/smell (i.e. "smell" has two meanings, one for the activity of sniffing out - ('The dog was smelling my shoes'), and the other for a more passive kind of reception of some smell.) In his celebrated 1966 The Senses Considered as Perceptual Systems J.J. Gibson argued that the active seeking out of "information" is more fundamental than passive sensing, and his famous cookie-cutter experiment showed this. If you actively move your hands relative to the object of perception, the percentage of correct identifications is very high. If the stimuli are given to you passively, the percentage drops to under half of what it was. The senses have to be active, and without activity even the passive sensation degrades. This was also shown by some early phenomenological experiments by Katz on...

I want to ask about the truth, universal truth. There is any standard about universal truth?I mean the truth which every one agree about it. what is the real truth? Why people have their own argument about their own truth? is it possible all of people agree about one truth?

Do you really believe that there is any truth that you are going to get 7,511,772,360 (the number on the rolling world census at the time of writing) people to agree to? That includes new born infants, who are people. So perhaps we should cut off your question at some later age, say 18. But how will this age be decided? I think probably people have their own views because they have their own ideas, and they have their own ideas because their experiences are different and they are very different people anyway. Still, most people, though by no means all, accept elementary mathematics and the elementary ethics of everyday life. There are standards of evidence and argument that apply to both, to ethics in practical settings and to mathematics in theoretical ones as well. It seems very improbable that short of the coming of the Kingdom of God everyone will agree on everything. But that doesn't mean that what they should agree on, because it is true, isn't true.

Philosophers like Wittgenstein and Plato are known for their distinctive, and challenging, writing styles. Perhaps unsurprisingly, commentators generally don't write like Wittgenstein and Plato in writing about them. Does this show that works like the Tractatus and the Republic could have been written just as well in ordinary prose? My underlying presumption here is that when people write about philosophers, this largely amounts to restating the claims of those philosophers. So if a Wittgenstein scholar insists that Wittgenstein's oracular style is essential to his philosophy, and yet argues as much in an article written in straightforward, conventional prose, she is actually contradicting herself in a way.

Not all of Plato's writings are challenging or difficult. But some are, the Parmenides for example. And Wittgenstein writes perfectly ordinary sentences in the Philosophical Investigations , though people complain that the writing is hard to follow. I can't agree with this, as I think it's a view that insinuates itself when you don't know the arguments very well. The Tractatus is of course different. But both the Parmenides and the Tractatus could have been written in ordinary prose, apart from the symbolic bits, for example in connection with the symbol omega and the theory of numbers, say, or the theory of truth-functions and the general form of the proposition. But your presumption is wrong. When people write about philosophers' work, very little restates the claims of those philosophers. The only point of that would be educational. Much more of the writing about works of philosophy is about what the claims mean and whether they are true. So your contradiction disappears. It is...

Is their really an objective answer as to where the world came from?

The current evidence and theory from cosmology almost conclusively give us the objective answer that the first event was the Big Bang. If God brought about the Big Bang, that too is an objective answer, or if the Big Bang came about due to fluctuations in a sea of quantum gravity, that is an objective answer. As Stephen observes, the steady state theory (the universe was always there) is equally objective. The Big Bang and the steady state theory may be counter-intuitive, but they are objective answers. You ask about the existence of an objective answer to the cosmological question in particular. I cannot see anything about the question where if anywhere the universe came from that raises questions of objectivity. Or is there a religious question behind your question? Does your question really mean, 'Is there an objectively true answer as to where the world came from, rather than a religious answer?' Then is the assumption that religion is subjective? That may be all wrong about what is behind your...

A lot of philosophy seems to be "philosophy of x" -- philosophy of science, philosophy of language, philosophy of mathematics, etc. Given this, should philosophy, institutionally speaking, be treated as a separate discipline at all? I mean, why couldn't the various philosophies of x be absorbed into the various types of x?

What you are offering is a philosophy of philosophy. From your principle that "philosophy of x" should be absorbed into the department of x, institutionally speaking, doesn't it follow that philosophy of philosophy should be absorbed into the department of philosophy? But it must be treated as "a separate discipline" for this to happen. Where else would you teach the philosophy of philosophy, metaphilosophy? In the department of physics perhaps?

What is the difference between marital relationship and a committed relationship in all aspects, except the legal bond? there really a difference?

The difference is exactly that marriage is a legal bond, and it involves certain obligations and requirements (for example those having to do with property) that may not be implied by the "committed relationship". It is as a result a more serious affair. There is also the historically related fact that marriage is often taken to have a religious dimension, which the committed relationship may or may not. What some people dislike about marriage is that in the past it has existed in a hierarchical setting, so that a priest or other official, at a particular moment, says the words, 'I pronounce you man and wife.' It may be that in a particular committed relationship there is such a moment, but it may also not be the case.

Hi, I'm a biology student who often uses biology as a framework for understanding thought. I've come to a really tough crossroads of thought. What differentiates cognitive biases from logical fallacies?

The difference between the cognitive biases and the logical fallacies is that the biases can be taken to be common built-in tendencies to error of individual judgements , whereas the fallacies, both formal and non-formal (so-called "informal", badly named because "informal" actually means "casual" or "unofficial" or "relaxed") are types of argument . The point is that the biases can be said to have causes, and are hence of psychological but not logical interest, whereas the fallacies do not have causes (though the making of a fallacy on a particular occasion may have) and the reverse is true. There is more to be said, of course, because a psychologist might take an interest in the fallacies.

I would really like to know what logic is. The Stanford Encyclopedia of Philosophy has TOO MANY articles on logic for someone like me. Let me list most of them: action logic, algebraic propositional logic, classical logic, combinatory logic, combining logic, connexive logic, deontic logic, dependence logic, dialogical logic, dynamic epistemic logic, epistemic logic, free logic, fuzzy logic, hybrid logic, independence friendly logic, inductive logic, infinitary logic, informal logic, intensional logic, intuitionistic logic, justification logic, linear logic, logic of belief revision, logic of conditionals, logical consequence, logical pluralism, logical truth., many-valued logic, modal logic, non-monotonic logic, normative status of logic, paraconsistent logic, propositional dynamic logic, provability logic, relevance logic, second-order and higher-order logic, substructural logic, temporal logic. I have started reading some of these articles, but I still didn't find an answer for my basic question. In...

There are "forms" of thinking and reasoning and arguing that do something very specific. They guarantee that if the premises of your thinking and reasoning and arguing are true, then so is your conclusion. These "argument forms", as we can call them, are said to be "valid". Logic is the study of these forms, and the methods used to distinguish them from invalid forms. An example? Well, what about De Morgan's theorems, one of which states not-(p AND q) is the same thing as (not-p OR not-q). This is valid, and it is worth studying, even for its intrinsic interest. And if you do study it, what you are studying is logic, or a part of it.

Assuming that trees are not conscious, is there anything morally wrong with cutting down a tree that has survived for a thousand years?

It is most certainly not true that non-conscious things can be destroyed without reason, or just for the reason that they are not conscious. What is wrong with slashing or burning a Rembrandt painting? The answer is not that there is nothing wrong, because the painting is not conscious, but that there are many things wrong, including aesthetic ones, and historical ones, and the fact that the painting does not belong to to the slasher. Of course it would be even worse if the painting were conscious. And even if it belongs to the one who destroys it, it is unclear that he has the right to destroy it. A question might still arise. Is the painting part of the national heritage? This sort of consideration is relevant with Grade I, II* and II listed buildings in the U.K. Or what would be wrong with burning the only Penny Black remaining in the world just for kicks? About the 1000 year-old tree, now. The mere fact that it has survived for that long, for nearly 1000 years since the Norman Conquest, to put it in...