06b. Locke, Berkeley, & Empiricism. Part 2/2.
Locke believed that the distinction between primary and secondary qualities explained the disagreements that we all have about our perceptions of the outside world.
Like, we could measure this apple in a bunch of ways and all agree on its primary qualities, but its secondary qualities would no doubt lead to some disputes.
Like, is it really red? What kind of red exactly? Cardinal red? Or carmine red? It's kind of dark purple at the top -- or is it just like a dark pink? What about the sound it made?
Would I call that crunchy? Or crispy? Or...bite-y? It's like, apple sound. We could argue about that kind of stuff til the cows came home. But if we disagree about its primary qualities – one of us is simply wrong. Because primary qualities have nothing to do with you, or me. Instead they have everything to do with the object itself. Locke's reasoning was simple, even elegant, extracting a lot of explanatory power out of very few basic concepts. As a result, it resonated with a lot people. And one person it resonated strongly with was the Irish philosopher George Berkeley. He was moved by Locke's empiricism and took it seriously -- so seriously, in fact, that ended up using Locke's own logic against him.
He basically took empiricism to its logical conclusion, dismantling the whole process of perception to the point that he had to wonder whether anything existed at all. Berkeley began by taking apart the distinction that Locke made between primary and secondary qualities.
Like, think about this apple again. How do you know its shape? Locke said that the apple's shape, as a primary quality, is immediately perceivable. But Berkeley pointed out that you don't perceive some qualities of an object, while totally disregarding others. Like, you can't detect an apple's shape without first -- or at least without also -- detecting its color. When you think about it, you can't detect any of the primary qualities without also considering the secondary ones. You can't see a colorless apple.
You can't feel a textureless apple. In fact, if you try to strip away the apple's secondary qualities in an effort to get at the primary ones, you end up with no apple at all. Try it: Close your eyes and imagine an apple made of only primary qualities -- so, it has a certain shape and a certain size, but it doesn't have any color or texture or taste. You can't do it. You try to imagine it with no color, but really, you're probably imagining one that's either black or white or transparent -- the color of what's behind it. And if you try to imagine it as having no texture, you'll find there's still a texture there – it's just smooth. Remember: Locke asserted that secondary qualities are not objectively real.
They can only be subjectively perceived. But now, Berkeley has shown that the two are inextricably linked – you can't have one without the other. Which means that secondary qualities can't be real, either. They, too, are just what your mind makes of things. So this led Berkeley to a startling conclusion: There's just no such thing as matter.
There can't be! Instead, there's only perceptions. Berkeley's famous assertion -- his version of cogito ergo sum -- was esse est percepi: “to be is to be perceived.” In his opinion, there are no objects, only perceivers – and even then, the perceivers themselves don't really have any physical form.
They're just disembodied minds perceiving things that aren't really there. A little bit terrifying when you start thinking about it.
In Berkeley's scenario, we're all set adrift in a world of nothing but thought. What's scary about it is this, if everything's just perception, then when the perception goes away, there can't be anything left. So like, please, for the love of Pete, do not turn away from your computer!
If you stop perceiving me, I stop existing! But, what if maybe you don't care about me? Still, you'd better not go to sleep, because as soon as you do, you'll cease to exist! Because, you won't be able to perceive yourself! The only guarantee that you'll continue to exist in your sleep is to have a friend watch you when you're sleeping. Which probably is a non-starter, for a number of reasons. But in any case, the second your friend blinks, you're gone! So in the end, Berkeley believed there was only one thing that kept us -- and everything else -- from disappearing into oblivion.
God. Berkeley believed that God was the Ultimate Perceiver. God is always watching, with unblinking perception that holds objects in existence even when we're not paying attention.
The tough thing about Berkeley is, we all pretty much think he has to be wrong.
Very few of us are willing to give up our belief in the physical world — no matter who's watching. We are sensory animals! We really need this apple to exist. Next time, we're going to take a side journey into the world of knowledge.
And then, in episode 8, we'll see if Karl Popper can manage to get the physical world back for us. Today we have learned about empiricism as a response to skepticism.
We talked about John Locke and his distinction between primary and secondary qualities. And we've seen why George Berkeley thinks that distinction ultimately falls apart -- leaving us with literally nothing but our minds, ideas, and perceptions. This episode of Crash Course Philosophy is made possible by Squarespace.
Squarespace is a way to create a website, blog or online store for you and your ideas. Squarespace features a user-friendly interface, custom templates and 24/7 customer support. Try Squarespace at squarespace.com/crashcourse for a special offer. Crash Course Philosophy is produced in association with PBS Digital Studios.
You can head over to their channel to check out some amazing shows like Idea Channel, The Art Assignment, and Gross Science. This episode of Crash Course was filmed in the Doctor Cheryl C. Kinney Crash Course Studio with the help of these awesome people and our equally fantastic graphics team is Thought Cafe.
