After a lengthy (around 4 hours) discussion among our roommates, we came along with a common definition of what is commonly referred to as a “sandwich”: 

- Article 1: A sandwich is a dish consisting of a container and a filling. 

- 1.1: The container must consist of one or two connected parts 

- 1.2: It must be possible to retrieve the container without destroying it 

- 1.3: The container must consist of a starchy base.

- Article 2: The sandwich must be able to be eaten in public without any non-edible third-party items (including tables, cutlery, napkins, and so on).

- Article 3: The customary way of consuming the sandwich must be compatible with the process described in Article 2. 

Note: The sandwich is culturally defined; therefore, Article 3 is based on cultural criteria. In case of doubt, Articles 1 and 2 take precedence.

Everything here have been debated from an occidental and french persoective.

Me and my roommates would be very happy to explore new perspectives and contradictions as it would force us to make a more precise definition of the sandwich

According to us, hot dog is a sandwich as it fullfill article 1 and 2

Yes. A few weeks ago, some coworkers and I mapped out the entire sandwich taxonomy. You attain sandwich nirvana once you derive these definitions:

1. Hot dog is a taco.
2. Taco is a subcategory of sandwich.
3. If the sandwich contains an additional piece of bread inside of it, it is now a lasagna.
4. Lasagna is a subcategory of sandwich. 🤯

Now it all makes sense. Be at peace.

A hot dog is a taco. See: https://cuberule.com/

It is a taco.

A hot dog is a taco

If a hoagie or hero is a sandwich, then it is only logical that a hotdog is also a sandwich.

EDIT: Since my criteria here has been cited by others and this comment, as initially presented, contributes very little to the discussion, I am amending this comment with the following information: Based on Ken Burns' Baseball documentary (at least my memory of it; been a few years), the hot dog has its genesis with guys selling food outside of a baseball park. They were selling sausages that were coiled, and served on a bun. The buns ran out and so they grabbed some Italian bread sold nearby, cutting the sausages and laying them in the bread, sliced sideways. This posits that the foundational concept of the hotdog was a conventional sandwich.

No. It's in the subcategory of bread based meals like sandwiches and pizza, scones, etc. The topology is different. Sandwiches are built with layers. Hot dogs have a bread cup/container with extra condiments wedged on top.

Hot dogs also require a sausage. Sandwiches are agnostic to sausages.

This is what every Object Oriented Programmer is pondering on

a hot dog is a taco. is a taco a sandwich?

Neither it's a taco

What holiday features hotdogs as it's traditional food?

A hot dog is not a sandwich because most people do not call a hot dog a sandwich.

The definitions of words exist based on how we use them to communicate, not to fit into perfectly logical and consistent boxes.

A hot dog is a sandwich in the same way that tomatoes are a fruit.

yup

At one point I was pretty broke and bought the super cheap hotdogs and basic sliced sandwich bread for use as buns.
Still considered them to be hotdogs, despite being sandwich shaped.

I strongly believe that two (or more) separate pieces of bread are what defines sandwichness. Therefore, no, a hot dog generally uses a bun.

"Any object or objects that is "sandwiched" (i.e. surrounded in the middle) by another object or objects can be classified as a sandwich."

Tacos, hotdogs, burritos, hell even sushi, are all sandwiches.

I posit the most practical and likely least precise definition of all:

Whether something is a sandwich or not is like the difference between art and porn. You know it when you see it.

Could loads of things fall under a technical definition of a sandwich? Totally. Is a taco a sandwich? Please.

If it is, so am I - I'm wearing a jacket.

Yes. A sandwich can be closed on one and open on the other side

Only the Earl of Sandwich may designate what is or is not a sandwich. The original Sandwich sandwich was Roast Beef. Anything else is just sparkling white bread.

Given that a sub isn't a sandwich (no it isn't you uncultured filth sandwich is exclusively for the rectangle bread, the normal bread is a bocata, you call it sub) a hotdog isn't either. It's a sub for sure tho.