Brandeis University, Philosophy Department
Fall 2003
Brandeis University Web Stite

Philosophy 1A

Introduction to Philosophy

Professor Andreas Teuber
Prof. Teuber

"POP" Goes the Balloon
The Nature of Causation

The Balloon Experiment:
In the course of discussing how a person, any person, might get from his or her observations to the penny itself, I mentioned that you might wish to say that although you do not directly observe pennies in-and-of-themselves, your belief that is there, underlying your impressions, might be justified in light of your making a causal inference from what you observe, the penny, to your impressions of it, i.e., that the reasons you have impressions of a penny or of something penny-like, is due to the fact that a penny is causing those impressions. Now apart from the difficulties already raised with this line of reasoning, what about causation itself?

What is causation? Have you ever "seen" or observed causation in action?

Hold a balloon filled with helium in one hand. Hold on tight, we don't want it bouncing off the ceiling all night. Now hold a pin in your other hand. Now hold the balloon still with one hand and bring the pin slowly into contact with the balloon's surface, and do so with enough "umpf" to make the balloon pop. Did you see the pin make the balloon pop?

Perhaps you were not looking closely. Get another balloon. Perform the experiment again. Move the pin slowly towards the balloon's surface. Make it pop. Did you see? Did you see the pin make the balloon pop? You blinked? Don't blink. Try it again. Get another balloon. Move the pin slowly towards the balloon's surface. Don't blink this time. Perform this experiment over and over until you see the pin make the balloon pop. Or think you have seen it.

Now that you have seen the pin make the balloon pop, or think you have seen it, how would you answer someone who claimed that all you really saw was (1) the pin come into spatial contact with the balloon, followed by (2) the balloon's popping. How would you answer someone who said: "You never saw (did not see) the pin actually make the ballon pop."

Now this seems like an odd sort of thing to say and surely, one thinks, at first that it must be false. The swing of a golf club makes the golf ball sail down the fairway (or if you're new to the game or a bit of a klutz) into the rough). The cue ball moves the eight ball when it hits the eight ball into the corner pocket at the end of the game. What could be more obvious! Yet by paying close attention to what we actually experience in an instance of so-called causation, we never actually experience the cause producing the effect.

You don't really see the cue ball move the eight ball. You don't really see the golf club drive the golf ball. You don't really see the pin make the balloon pop.

What you see and all that you see is a sequence of events. First you see the pin in motion in your hand, then you see it touch the surface of the balloon, and then you see the balloon pop. And hence you can never be certain that balloons will always pop when they come into contact with pins addressed to their surfaces with sufficient "umpf."

You can never be certain that the future will resemble the past. That balloons will pop. That golf balls will sail into the distance when hit or that pool balls will roll when a cue ball is driven into them by the thrust of a cue stick. Or put another way: All we ever see are two events in regular spatio-temporal conjunction with one another and from this we infer that there is a binding relation between the two events, but we cannot see that they are bound together


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