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@tankgrrl @stevo399 @MostlyBlindGamer
The sixth.

@mees @MostlyBlindGamer I didn't! It seems to affect the middle finger a bit, too.
Currently beginning my dive into wikipedia's page about the flexor digitorum communis profundus!!

Pinky
@MostlyBlindGamer if you open your hands in front of you and read in the occidental left to right order, right thumb is 20 and left thumb is 29 (211 if your polydactyl). 1 is the index.
However you can also have your palm facing away and in this case the right ring finger would be 1. I don’t this it’s comfortable to count from pinky though.
When I'm counting for my own benefit and the number is in the range 0-10, 1-5 are right-little to right-thumb, and 6-10 are left-thumb to left-little. I am right-handed.
If I'm emphasizing numbers while talking, 1-5 is right-thumb to right-little, and 6-10 is again left-thumb to left-little.
I'm not sure it's particularly interesting or useful in itself.
I think my behaviour is affected by multiple things:
Expected number of items - if I know it will be in the range 1-3, I would emphasise the numbers from index to ring finger rather than from thumb.
Physical feedback - I think the reason I start with my little finger when truly counting is that I snap the fingers out from under my thumb which reinforces the sense of moving to a new state.
Social context - probably overrides all else.
Depends on what and how I'm counting.
Decimal or hex, index finger following ASL, left hand is the tens or sixteens column.
Binary counting up, thumb.
Binary converting to decimal, left middle finger.
@MostlyBlindGamer thumb, but four is the other four fingers extended and then I move my thumb again for five. I've been told that's strange.
I count multiples of six on the other hand, so using only my fingers I can count up to 35 instead of 10.
@MostlyBlindGamer Usually thumb, except if I'm in front of students. Then I use the Chinese method because I always have at least one student from China and it can lead to a whole conversation about intercultural stuff and international business, etc.
Best one is getting students to decide if the "making a circle with index and thumb" means OK, Zero, or something awful.
@MostlyBlindGamer could be either. Pinky is a less used option. When using both hands, left hand starts at the same finger the right one ended at.
When signalling to other people, index first.
This being a shibbolith was a plot point in "Inglorious Bastards", IIRC?