Can We Ever Be Sure of Our Opinions?

The reasons why knowledge is unreliable.

Bertrand Russell is notorious for having a clear way of describing central traits of reality and the big concepts of philosophy to regular people. He was the intellectual that made philosophy accessible to our generation.

Short Biography

Russell lost a lot of his close family at a young age, including both his parents, by the age of 5. He was because of this raised by his very religious Presbyterian grandmother.

He contemplated suicide because of his upbringing, but his desire to learn mathematics prevented him from doing it. You heard it.

When he was 18 he denounced Religion, which he became famous for, after his collection of essays, Why I am Not a Christian.

He is also famous for writing one of the best introductions to the major themes of philosophy.

Problems of Philosophy

“Great spirits have always encountered great opposition from mediocre minds” (Albert Einstein defending Bertrand Russell).

In this blog post, I wanted to discuss in greater detail the first three chapters of the book, namely the ones that deal with the study of knowledge.

He writes about some of the major themes of philosophy and explains why they so crucial. He discusses Appearance vs. Reality, The Existence of Matter, How A Priori Knowledge is Possible (Knowledge that is not based on experience, but rather on given truths, such as Mathematics), The Limits of Philosophy, and among other things, The Reasons to Study Philosophy.

“The value of philosophy is, in fact, to be sought largely in its very uncertainty” (Problems of Philosophy, 156).

In the first three chapters, Russell tackles the question of Reality, whether we can be certain of that which we can feel, see, or hear. Despite how easy the answer to this question may come to us, he says that this question is, “really one of the most difficult that can be asked.”

The problem arises when you walk into a room with, let’s say, a table. If there are a few people in the room, it follows that no two of them will see the table with exactly the same distribution of colors, because no two are looking at the table from the same angle. So for the person viewing the table, it is clear that the table never actually has one color, but is dependent on the light in the room and the angle of viewing the table.

The same applies to the taste of an apple. The flavor is given to us because of the taste-buds we have, due to the way we have been evolved. The bird, plucking away at the apple, does not sense the same flavor from the apple. So if the apple’s flavors do not exist universally from the senses, does it exist at all? Why would we suppose that we have the correct sense of the apple’s true flavors?

So it is with the table.

“Thus it becomes evident that the real table, if there is one, is not the same as what we immediately experience by sight or touch or hearing. The real table, if there is one, is not immediately known to us at all, but must be an inference from what is immediately known.”

He then introduces Descartes (1596–1650), the “founder of modern philosophy.” Descartes tried to disprove skepticism by putting himself in the shoes of the skeptic. He tried to doubt everything to the extent of doubting his own existence.

Descartes concluded that doubt concerning his own existence was not possible since there must have been someone that doubted his thoughts, which had to be himself. With this he showed that subjective things, such as one’s existence, is certain.

“Descartes performed a great service to philosophy, and one which makes him still useful to all students of the subject.”

He then elaborates on the certainty of ourselves by asking if we can be certain of that which is around us — the outside world. We have to find in our experiences, some sort of characteristics that other people can experience as well.

Reality vs. Dream

Is that logical absurdity? Well Russell points to dreams, which are very real for the person that is in them, but entirely delusional.

Recently I had a dream about someone knocking very hard on my bedroom door, I woke up startled wanting to open the door. But I laid in bed in the expectation that the person would knock again. Yet no one knocked and no one walked away from the door. The dream, however, was completely real, but far from reality.

The reason we can know that the table exists is that if we shut our eyes to not see it, or step away from being able to touch, we are still capable of opening our eyes or touching it again. It exists independently of our perception of it.

Idealists take this a step further. They deny that matter exists as something separate from the mind, though they do not deny that “sense-data” (mind independent objects whose existence are known to us primarily because of our perceptions) are something that exists independently of our senses. Russell would disagree with this point of view, which he then elaborates on in Chapter 4.

If you want to read more about that, get yourself a copy of his book Problems of Philosophy. And if you are interested in more stuff like this, make sure you follow me! I publish things on philosophy fairly often.

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I write to keep you thinking and to keep me thankful and reflective. Cheers cheers cheers and until next time,

keep reflecting.



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Jakub Ferencik

Author of “Up in the Air” & “Beyond Reason” available on AMAZON | MA McGill Uni | Research assistant for EUROPEUM Prague | 550+ blog posts with 1+ mil. views