I'm sure this has been discussed before, but I wasn't able to find the answer. Why doesn't a saddle go onto a saddle post which is inserted into a saddle tube which connects to saddle stays?

I think a majority rule of "seat-" parts would instead ask, "Why is the seatpost connected to a saddle and not a seat?"

because it's easier to say seat post instead of saddle post? I dunno. Why not?

I thought it was a "pillar"

You should park your seat in the saddle and stop asking questions.

My seat post has a seat on it.

Well in my experince a saddle when talking about a bike is a full leather seat.
Anything else is a seat. I have never heard anybody call anything but a full leather seat a saddle.
It seems to be that if it has padding at all it is a seat.

Dictionary.com provides the 1st and 2nd definition of a saddle as a "seat" -
but I think the operative word here is "rider" as opposed to "sitter".

sad·dle
   /ˈsædl/
–noun
1. a seat for a rider on the back of a horse or other animal.
2. a similar seat on a bicycle, tractor, etc.

I think you straddle a saddle, but sit on a seat. Brooks Pro is a saddle, while B67 is verging on seat. And anyway, it's a seat pin, not post. Furthermore, the French (and maybe Italians?) don't have this issue: Selle and Tige de Selle. But they have other issues!

For the same reason you park in the driveway and drive in the parkway.

Because it hurts if the seat post is on the saddle

The seat tube used to be called the "saddle post mast", the down tube was called the "lower reach tube", the head tube was called the "steering head", seat stays were called "upper stays", the bottom bracket shell was called the "crank hanger", chain stays were "lower stays", the top tube was the "upper reach tube", the seat post was called the "saddle post", etc....

This terminology was used in Frank W. Schwinn's patent application for the cantilever frame in 1938.

"Why is a saddle put on a seatpost?"

I believe, but have never tried, to put ones seat upon the post fearing it would certianly hurt, thus the saddle is put atop said post and the seat is placed upon the saddle to remove such well founded fears.

I don't know the answer, but if you don't like saddle on the seatpost, then just take the saddle off and sit on the seat post.

My understanding is that saddles and seats are NOT the same thing and it has nothing to do with padding, springs or leather. A saddle is something that takes partial weight while a seat takes full weight. For example, a saddle on a horse...you use the side of your legs to support weight as well as your arms. A recumbent bicycle would have a seat. I was wondering why people finicky enough to use the term saddle would also use the term seat post.

+1!

Fewer syllables.

Same reason they climb mountains, because it's there.

That's a great point.

Why Does a Saddle go on a Seat Post?

1-to prevent unintended intimacy between the rider and seat post.....

....this for a whole list of reasons.

Mine too.

Uh-oh, we don't want to call it the "buttpost" now, do we?

You heathens, the correct terminology is,

The sella is attached to the reggisella which is inserted into the tubi verticali that is supported by the tubi posteriore.

Since in my opinion you need to go to the OED to understand the English language and its origins, here is the definition from that source:
saddle


• noun 1 a seat with a raised ridge at the front and back, fastened on the back of a horse for riding. 2 a seat on a bicycle or motorcycle. 3 a low part of a hill or mountain ridge between two higher points or peaks. 4 the lower part of the back in a mammal or fowl. 5 a joint of meat consisting of the two loins.
• verb 1 put a saddle on (a horse). 2 (be saddled with) be burdened with (a responsibility or task).
— PHRASES in the saddle 1 on horseback. 2 in a position of control or responsibility.
— ORIGIN Old English.


Note that the important criteria is the raised ridge front and back: so saddles are a particular type of seat with a raised front and back. So all you folks with your brooks' done up too tightly, you've converted your saddle to a seat


Mark (resident pedant)

Here's another way to look at it. You ride on a saddle. You drive in a seat. Driving implies control solely by mechanical means of control (i.e steering wheel, throttle brakes). Thus you drive a car, truck or tractor. Riding contains additional elements of control (i.e. balance, shifting of body weight). Thus riding is the preferred term for bicycles and motorcycles.