The fox mugs

About this video

Lena and her brother Tom were each given a mug for their birthday, and the two mugs are exactly alike: blue, with a little orange fox on the side. One morning Lena sees Tom drinking from a fox mug and says, "That's my mug!" Tom says, "No, it's the same as yours - but it's mine." Who is right? It depends on what "the same" means.

"The same" has two meanings in everyday talk. The first is exactly alike: two things with the same properties. Lena's and Tom's mugs are exactly alike - same colour, same shape, same fox - but there are two of them, and if Tom breaks his, Lena's is still on the shelf. The second is the same one: not two things but one. When Lena asks "Is that my mug?" she isn't asking whether it looks like hers; she is asking whether it is the very mug she was given. To tell the two apart, ask: how many are there? Two things exactly alike are still two; something that is the same one is one.

Long ago people saw a very bright star low in the sky just before sunrise and called it the Morning Star, and a very bright star just after sunset and called it the Evening Star, and thought these were two stars. Astronomers later worked out that they are one and the same: the planet Venus, seen at different times. Nothing about Venus changed; people found out that two names pointed to one thing.

The two meanings can come apart the other way too. Kofi's apple went from red and crunchy to brown and soft in a week. The apple then and now are not exactly alike, but they are the same one: there was only ever one apple. So a thing can change and still be the same one - which raises the question of how much it can change. This video goes with the Two Ways of Being the Same lesson of Metaphysics Level 1 on Knaph.

Transcript

1. 0:00Lena and Tom have fox mugs, exactly alike. That's my mug, says Lena.
2. 0:05Exactly alike means the same properties. But there are still two mugs.
3. 0:11The same one means one thing, not two. Ask, how many are there?
4. 0:17The Morning Star and the Evening Star turned out to be one. Venus.
5. 0:23Kofi's apple changed. Not alike, but still the same one.
6. 0:29Exactly alike, or the same one?