It ought to be possible to restore to the word "philosophy" its original meaning: philosophy − the "love of wisdom" − is the science of all the fundamental principles; this science operates with intuition, which "perceives," and not with reason alone, which "concludes". Subjectively speaking, the essence of philosophy is certitude; for the moderns, on the contrary, the essence of philosophy is doubt: the philosopher is supposed to reason without any premise (voraussetzungsloses Denken), as if this condition were not itself a preconceived idea; this is the classical contradiction of all relativism. Everything is doubted except for doubt. The solution to the problem of knowledge − if there is a problem − could not possibly be this intellectual suicide that is the promotion of doubt; on the contrary, it lies in having recourse to a source of certitude that transcends the mental mechanism, and this source − the only one there is − is the pure Intellect, or Intelligence as such.

We must never forget that it is principles, not phenomena, — laws not insulated independent facts, — which are the objects of inquiry to the natural philosopher. As truth is single, and consistent with itself, a principle may be as completely and as plainly elucidated by the most familiar and simple fact, as by the most imposing and uncommon phenomenon. The colours which glitter on a soapbubble are the immediate consequence of a principle the most important, from the variety of phenomena it explains, and the most beautiful, from its simplicity and compendious neatness, in the whole science of optics. If the nature of periodical colours can be made intelligible by the contemplation of such a trivial object, from that moment it becomes a noble instrument in the eye of correct judgment; and to blow a large, regular, and durable soap-bubble may become the serious and praise-worthy endeavour of a sage, while children stand round and scoff, or children of a larger growth hold up their hands in astonishment at such waste of time and trouble. To the natural philosopher there is no natural object unimportant or trifling. From the least of nature's works he may learn the greatest lessons. The fall of an apple to the ground may raise his thoughts to the laws which govern the revolutions of the planets in their orbits; or the situation of a pebble may afford him evidence of the state of the globe he inhabits, myriads of ages ago, before his species became its denizens. And this, is, in fact, one of the great sources of delight which the study of natural science imparts to its votaries. A mind which has once imbibed a taste for scientific inquiry, and has learnt the habit of applying its principles readily to the cases which occur, has within itself an inexhaustible source of pure and exciting contemplations. One would think that Shakspeare had such a mind in view when he describes a contemplative man as finding

We should remember that there was once a discipline called natural philosophy. Unfortunately, this discipline seems not to exist today. It has been renamed science, but science of today is in danger of losing much of the natural philosophy aspect.

Philosophy must be of some use and we must take it seriously; it must clear our thoughts and so our actions. Or else it is a disposition that we have to check, and an inquiry to see that this is so; i.e. the chief proposition of philosophy is that philosophy is nonsense. And again we must then take seriously that it is nonsense, and not pretend, as Wittgenstein does, that it is important nonsense!

Philosophy shows itself to be alive when it raises, again and again, the deep concerns that plague man's reason; it dies when it presumes to have resolved them with finality. Determinism and freedom in their conjunction pose one of the eternal questions ...

The basic drive behind real philosophy is curiosity about the world, not interest in the writings of philosophers. Each of us emerges from the preconsciousness of babyhood and simply finds himself here, in it, in the world. That experience alone astonishes some people. What is all this — what is the world? And what are we? From the beginning of humanity some have been under a compulsion to ask these questions, and have felt a craving for the answers. This is what is really meant by any such phrase as "mankind's need for metaphysics."

The natural philosophy of the new developments in the sciences is a systems philosophy. When properly articulated, it can give us both factual and normative knowledge. Exploring such knowledge and applying it in determining our future is an opportunity we cannot afford to miss. For if we do not, another chapter of terrestrial evolution will come to an end, and its unique experiment with rational consciousness will be written off as a failure.

Some people criticize philosophy as pointless navel-gazing. But there is a lot more to it than just that. There’s also a lot of beard-stroking: and to my experience, quite a lot of arrogant condescension too.

The word "philosophy" carries unfortunate connotations: impractical, unworldly, weird.

Philosophy when superficially studied, excites doubt, when thoroughly explored, it dispels it.

Since the word "knowledge" occurs in my general title... I am going to be talking about epistemology, although I prefer to use the eighteenth-century, indeed, medieval phrase, "natural philosophy." ...that enterprise of the human mind which attempts to trace lawfulness to nature, dead and living, but which is not directed to specific inquiries into how this or that law works. Philosophy in the sense in which I practice it, natural philosophy, is concerned with lawfulness rather than with laws and the general nature of laws rather than with the specific structure of this or that law. Natural philosophy was one of the three topics (moral philosophy and metaphysical philosophy were the others) to which one graduated in medieval universities after having studied the seven liberal arts.
I believe that we need to review the whole of our natural philosophy in the light of scientific knowledge that has arisen in the last fifty years.

What's the good of a philosophy with a major premise that isn't the rationalization of your feelings? If you've never had a religious experience, it's folly to believe in God. You might as well believe in the excellence of oysters, when you can't eat them without being sick.

The trouble I have with astrophysics or quantum mechanics is the same problem I have with philosophy; which is: initially it is mind blowing, then it is fascinating, then it is disturbing, then it is almost uncomprehensible, then it's fascinating again, then you disappear up your own ass.

Here, as usually in philosophy, the first difficulty is to see that the problem is difficult. If you say to a person untrained in philosophy, "How do you know I have two eyes?" he or she will reply, "What a silly question! I can see you have." It is not to be supposed that, when our inquiry is finished, we shall have arrived at anything radically different from this unphilosophical position. What will have happened will be that we shall have come to see a complicated structure where we thought everything was simple, that we shall have become aware of the penumbra of uncertainty surrounding the situations which inspire no doubt, that we shall find doubt more frequently justified than we supposed, and that even the most plausible premisses will have shown themselves capable of yielding unplausible conclusions. The net result is to substitute articulate hesitation for inarticulate certainty.