Empiricism – From Locke to Hume
Empiricism is an epistemological theory (or, a theory of how we know stuff) that is primarily concerned with sensory experience. Empiricists believe that all knowledge comes from our senses, and from actually physically experiencing the world. They DO NOT think there are any innate ideas, ideas that are held in the mind a priori, or independently of experience. Empiricism is more or less the direct contrast of rationalism: the rationalists (like Descartes, who I talked about last week) believe that all knowledge comes from reason alone. They don’t trust sensory experience because our senses can be deceived; but pure reason cannot be.
Put simply – Rationalists think that if you grew up in a locked room with no windows, you could gain knowledge of the world simply by thinking about it, thanks to the innate ideas in your mind. Empiricists think you actually have to go out and experience the world, in order to gain knowledge of it.
Two of the most prominent empiricist philosophers, are John Locke and David Hume.
John Locke (1632-1704)
Locke was an English philosopher, and one of the foremost thinkers of the Enlightenment. In fact, he is often referred to as the “Father of the Enlightenment”, because he was so influential.
Contrary to Descartes’ view, Locke posits that the mind is a tabula rasa, or blank slate, at birth. There are no innate, or God-given, ideas in the mind, only the capacity to have them (an innate capacity to reason). All of our knowledge must come from experience of the physical world, through sensory perception.
Locke’s chief argument against innate ideas, is that if such ideas existed, they would be universal in all men. However, he argues, there is not one single idea that is universally held. Previously, rationalists had argued that some ideas, such as morality and the idea of God and his goodness, were innate and universal, but Locke raises the point that there are many examples of people who have no conception of these ideas, such as children and the mentally ill. (Who he refers to as idiots. Yes, really.)
He also introduced the idea of simple and complex ideas, to distinguish between ideas that we gain through sensory perception, and ideas that we create in our minds. Simple ideas are the impressions we gain from sensory perception, i.e. the taste of something, or it’s colour or texture. They are the building blocks that allow us to create complex ideas in our minds. Complex ideas are the result of combining our raw sense impressions, for example, combining the ideas of roundness, fuzzy texture and the colour yellow to get the idea of a tennis ball.
David Hume (1711-1776)
Scottish philosopher, David Hume, is widely regarded as one of the greatest philosophers in modern history, and certainly one of the last great British empiricists.
Like Locke, Hume believed that the mind is a blank slate at birth, but disagrees with the idea that we possess the innate capacity to reason. Hume believes that there are NO innate ideas or capacities within us, but that EVERYTHING is acquired through experience, including our capacity to reason and hold ideas.
Hume thought that all ideas come from two types of experience: outward and inward impressions. Outward impressions come through our senses, while inward impressions come from internal reflection. Hume’s idea of outward and inward impressions is similar to Locke’s theory of simple and complex ideas; outward impressions are simple ideas gathered through sensory experience, while inward impressions built upon our previous experience, that allow us to have ideas of things we have not/could not experience e.g. we can think of a golden mountain, even though we can never experience one, by combining the ideas of gold and of a mountain.
Hume also forms a strict division between relations of ideas (a priori knowledge), and matters of fact (a posteriori knowledge)*. Hume says a priori knowledge, gained through deductive reasoning, can tell us nothing new about the world, so he doesn’t spend as much time examining it. His thoughts on a posteriori knowledge though, led him to the induction fallacy.
Inductive reasoning, looks at past experience, and assumes the future will conform to this. All a posteriori knowledge is based on induction, we see green grass, and assume all grass is green. The sun rose yesterday, and the day before, and the day before, as it has done all our lives, so we assume it will rise tomorrow. This is induction.
But Hume argues to base any knowledge on previous experience is foolish, because the past is no guarantee of the future. Yes, the sun may have risen yesterday, but we can never know for certain that it will do so tomorrow, only assert that it will, with a high degree of probability. There are no natural laws states Hume.
Expanding on this slightly, Hume applies the induction fallacy to miracles. Miracles, he says, do not exist; a miracle is merely an event which doesn’t conform to our natural laws. He gives us a great line, “Extraordinary events require extraordinary proof.” The more amazing an event is, the more proof you need to accept that it happened.
So that’s empiricism in a nut-shell. A very basic run-through, with a lot of the tasty nutty bits removed, but that’s what you get when you order things in the quantity of nut-shells!
Till next time.
*Hume’s aggressive separation of all knowledge into these two categories led to the criticism from more recent philosopher’s, known as Hume’s Fork.