The ICAS Lectures


The Limits of Human Understanding

Yuliana Sara Noah

ICAS Summer Symposium
The Korean Diaspora

August 4, 2007 Saturday 9:30 AM - 4:30 PM
Montgomery County Community College Science Center room 214
340 DeKalb Pike, Blu Bell, PA 19422

Institute for Corean-American Studies, Inc.

965 Clover Court, Blue Bell, PA 19422


The Limits of Human Understanding 1

Yuliana Sara Noah 2


I was fascinated by the in depth analysis John Locke 3 makes of human understanding. This topic was particularly interesting to me since I have always been intrigued by psychology of the human mind and how knowledge is obtained. Locke explains that the mind of a newborn child is like a sheet of white paper 4 waiting to be filled with knowledge. As the baby grows up, he experiences situations in life that causes the mind to slowly be filled with ideas, opinions, and knowledge, ultimately leading to understanding; Locke explains this process as the steps to understanding. John Locke’s entire essay is written out as a sort of mathematical proof. He first starts with one idea and proves it true through deduction, then build upon it. In the scientific world, Locke was the first to use the same logic in discovering mathematical truths and completely devoting that logic to our own minds. Locke is the father of empiricism because of his logical and orderly argument which gradually disproves each fundamental belief; those that had been generally accepted without reasoning. He starts with one theory, that no ideas are innate, and then goes on further to base his other theories and hypothesize upon it, eventually leading to complex ideas, perceptions, and finally human understanding.

The Limits of Human Understanding: Ideas are not Innate

The steps to understanding first start with an idea; Locke explains ideas as objects of understanding when man thinks. There are three levels to understanding, or knowledge, certainty, evidence, and extent. Once obtaining knowledge, one will form an opinion, faith or belief (being the assent to any proposition believed true even though there is no certain knowledge) about the information obtained. A person can perceive ideas through multiple facets, either through one sense only, more than one of the senses, by reflection, or also by sensation and reflection.

Many beliefs of the time were based on incorrect logic of the human mind; a problem which Hume 5 presents in his own writings. Man will use incorrect logic to prove his incorrect beliefs. Locke started from the beginning, proving one idea and eventually explaining the extent of human comprehension. The foundation of Locke’s mathematical proof starts with the theory that no idea is innate. Although we are not born with preexistent ideas, we are however, capable of attaining knowledge, which leads us to deduce that all ideas are formed after conception, gradually when a person experiences. Locke proposes that by examining human comprehension, we will find in what areas our brain fails us, so that we will not waste time on subjects that could never be understood by a human mind.

Locke once again uses deduction and logic of children to disprove innate ideas. All children learn principles which are the same as ideas. One might suggest that principles are guided with reason, which is innate, but this is also false. Reason is different to every person, just as principles are. For this hypothesis, he uses a thief. A thief knows no principle of justice in his conscience to stop him from stealing. Ideas like hot and cold, which may seem obvious, are also not innate. John Locke says the mind takes a particular idea and stores it in one’s memory, then abstracts it and makes a generalized name, like cold, that will apply to all objects.

The Limits of Human Understanding: Ideas Come from Experiences

As I was reading, the essay went on to further explore the human mind by dividing the mind into two categories, reflection and sensation. Sensation is experiencing externally while reflection is experiencing internally. Locke claims that the mind always thinks, and dreams are a result of our sleeping mind thinking, or the unconscious, as opposed to the awake mind, or the conscious. The conscious thinks adding the factor of the impression a certain event has on the body; the sleeping mind does not. That is why dreams seem to be random and not logical. However, in actuality I learned, our dreams are logical because the mind, while dreaming, is not affected by the impact on the body.

Not only are there two circumstances in which a mind thinks, there are also types of ideas that the mind creates. A theory that caught my eyes was one must notice in order to percept 6. Suppose that if we did not notice any object, we would not have the opportunity to have ideas about them. The body is able to perceive these ideas because of the different functions that the body is able to take on through the fives senses. This relates back to the mind because in all animals that sensation is changed by judgment. Since sensation is one of the types of ideas that the mind thinks in, judgment can distort views and give inaccurate evaluations.

This breakthrough in science, I feel, as many others do, is of the utmost importance to society today; learning that sensation is changed by judgment affects our lives daily. The addition of our own feelings and views into a situation often alters ones perspective and may cause one to make decisions irrationally. Extreme feelings like love and hate can prevent a person from making the best choice because of their own personal involvement in the situation. Men are more likely to choose what their passions are moved by. We pursue happiness, so the best and worst, or the good and evil actions, are only in reference to their pain which is another example of distorted actions.

Both Locke and Hobbes 7, see the importance of the conscious mind and unconscious mind as well as the train of thought, as Hobbes calls it. They both agree that the mind cannot stay on one idea for a long period of time; it is almost impossible to keep from wandering to other thoughts that the mind correlates to the previous. However, Hobbes then divides the train of thought into two categories, the wandering and regulated, which guides the mind to the next idea or thought according to the type of train of thought.

Although Hobbes and Locke both believed that ideas come from experience, they use different approaches to explain their theory. Hobbes discusses the way the mind comes across ideas, like Locke. But instead, Hobbes explains ideas through images that one sees throughout life. Even after the image is no longer present, the imprint of it exists in your imagination as a memory. With more images come more memory and more experience. The past images are dominated by the more present ones. In order to retain memories or remember information, the human mind must contemplate, revive memories and fix attention to memories that have been put aside. If not, memories will fade and one cannot retain it. He claims that the beginning of knowledge is not just retaining information. Although retention is a crucial first step to knowledge, other steps must also be taken for understanding. It is difficult to consciously break down the steps to knowledge because the human mind goes through all these steps almost instantaneously.

The Limits of Human Understanding: Words and Language

Words are important to gaining knowledge; words make names. We name everything that is of importance to certain society to allow communication of ideas. At the very beginning of language and communication, people created sounds to represent ideas. Then as time passed, people made new words using the same sounds. Eventually, men separated and altered words for convenience. Man tries to make words that will describe a specific idea but that can also be used to describe other ideas similar to that idea being named. Every civilization will have words for only the things that they have perceived in their society. This is one reason why a word in one language may not exist in another.

The Limits of Human Understanding: Knowledge

Finally, Locke defines knowledge. I’ve learned that knowledge is the perception of agreement or disagreement. To actually obtain knowledge, one must understand the identity and relation of two ideas, which are basically the similarities and differences.

The extent of our knowledge is all about comparison. John Locke states that our knowledge extends no further than we have ideas. For without ideas there would be no opportunity for relation and identity, which then prevents understanding. He also claims that knowledge can go no further than we can perceive their agreement or disagreement. To find if one is to agree or disagree, it is necessary to use intuition, reason and sensation. We then finally learn that knowledge is narrower than ideas 8. This may be because ideas can be fantastical or real and there is an infinity of situations that they could be presented with, in addition to the infinity of reactions to the situations. However, fantastical ideas will not happen in the natural world, which means there would be no opportunity to understand and compare them, so then we cannot possibly obtain the knowledge of that idea.

The Limits of Human Understanding: Extent of Human Understanding

Apparently, oblivion, slowness, and having a finite view are dilemmas that humankind must consider in order to find or avoid the areas in which we cannot possibly begin to comprehend. Discussing further our finite view, one finds that the mind cannot fix long on one invariable idea. And this theory leads to the fact that there are various degrees of attention while thinking. All of these hypothesize come into play when trying to obtain knowledge. Trying to think of one thing and only one thing seems to be an impossible task if experimented with. There are constantly ideas and images floating around in the mind. However, ideas are not actually in motion physically.

People use math and numbers as a way to compare or measure ideas. In the essay, I found that math is the most precise way of measuring all that is measurable. Therefore, numbers are relative and change according to the comparison of measures to one another. We then find that things that seem absolute actually contain relations. Math is also considered to be deduced, however, on the contrary, math is the reasoning of the maker, and once again, math is the study and comparison of the whole versus the part.

There are abstruse ideas like infinity that are difficult to comprehend because humankind tries to put a number or picture with something that is larger than time or duration. Although infinity is a mode of quantity, no one will be able to perceive infinity because it is so large.

Locke affected the works of future empiricists, like Hume, both believing the need for religion to comprehend complex ideas. Empiricism was based on probabilities, theories, and predictions, which rationalists like Leibniz 9criticized. Rationalism is the belief that the mind can obtain truth/knowledge without the need of senses. Leibniz, as well as other rationalists, uses methods to discover certain knowledge, differing from the theories of the empiricist, which is not founded by tangible evidence.


There were other scientists and philosophers before Locke that claimed there was indeed a limit to human understanding, like Chillingworth 10, however, Locke digs deeper to find exactly what our limits are. In order to explain the extent of our possible knowledge, he goes back to explain the origins of our minds, which basically consists of ideas from experiences from memories that are stored in the brain. From his thorough truths, Locke concludes that understanding is the outcome of the experience. We must have experiences to learn.

In conclusion, as I read John Locke’s essays, consisting of four books, I learned that ideas are not innate, ideas come from sensation and reflection of those experiences, ideas are communicated, through language, and finally in the fourth book, I have discovered the extent of human understanding that knowledge extends as far as ideas. John Locke was a true pioneer and father of philosophy. After three centuries, Locke’s theory is still very much alive today and will continue to be for many years to come. John Locke has influenced philosophers after his time from David Hume, a world renowned Scottish enlightened thinker, to the theorists today still exploring the human mind.

"Though the familiar use of the Things about us, takes off our Wonder; yet it cures not our Ignorance 11."

  • Berkeley, George. An Essay Towards a New Theory of Vision (1709) in Theory of Vision and Other Writing by Bishop Berkeley (New York: Dent and Sons, 1925).
  • Berkeley, George. A Treatise Concerning the Principles of Human Knowledge (1710) in British Empirical Philosophers ed. A.J. Ayer (New York: Carion, 1927).
  • Berkeley, George. Dialogues Between Hylas and Philonous (1713) in British Empirical Philosophers ed. A.J. Ayer (New York: Carion, 1927).
  • Burton, Robert. The Anatomy of Melancholy (1621; New York: Farrar and Rinehart, 1927).
  • Dell, Floyd. "Introduction", The Anatomy of Melancholy 1621; New York: Farrar and Rinehart, 1927).
  • Fraser, Alexander Campbell. "Introduction" to An Essay Concerning Human Understanding by John Locke (New York: Dover, 1959).
  • Hobbes, Thomas. Leviathan (1651; New York: Penguin, 1985).
  • Bacon, Francis. Advancement of Knowledge (1605; United States: Encyclopedia Britannica Inc., 1952)

Acknowledgement: I would like to thank Dr. Sang Joo Kim, Senior Fellow and Executive Vice President of ICAS for reviewing my paper and providing constructive feedback.

1 Review of essay, An Essay Concerning Human Understanding (1690; New York: Dover, 1959) by John Locke, prepared for presentation at the ICAS Summer Symposium: The Korean Diaspora, August 4, 2007, Montgomery County Community College, Blue Bell, PA 19422
2 A sophomore attending Moorestown High School, Moorestown, New Jersey
3 John Locke was a philosopher of the late seventeenth and early eighteenth century. His Essay Concerning Human Understanding aims to determine the limits of human understanding.
4 Berkeley, George. A Treatise Concerning the Principles of Human Knowledge (1710) in British Empirical Philosophers ed. A.J. Ayer (New York: Carion, 1927).
5 David Hume empiricist philosophical thinker of the 17th century England
6 Theory by John Locke, An Essay Concerning Human Understanding.
7 Thomas Hobbes, an empirical philosopher of the 16th century England
8 Theory by John Locke, An Essay Concerning Human Understanding.
9 Gottfried Leibniz rationalist philosopher 16th century Germany
10 Philosophical thinker of the seventeenth century in the Church of England
11 An Essay Concerning Human Understanding (III. vi. 9)

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