Are there only so many state-of-being verbs?

Question

This candy tastes so sweet.

Isn't 'tastes' a state-of-being verb? If it is why do people say there are only 8 state-of-being verbs - is, am, was, are, were, being, be, and been?

State-of-being verbs seem to be a fairly standard term.

Answer 1

I had never heard the term "state of being verb" before, but a quick Google search reveals that it is another word for linking verb, which I believe is the more official/accepted term.

A linking verb is something that links the subject with its subject complement.

Quoting University of Ottawa:

Linking verbs are either verbs of sensation ("feel," "look," "smell," "sound," "taste") or verbs of existence ("act," "appear," "be," "become," "continue," "grow," "prove," "remain," "seem," "sit," "stand," "turn").

Another tip from ChompChomp:

If you can substitute am, is, or are and the sentence still sounds logical, you have a linking verb on your hands. If, after the substitution, the sentence makes no sense, you are dealing with an action verb instead.

So in the example you cited:

The candy tastes sweet.

Tastes in this example would be a linking / state of being verb.

He tastes the apple.

Tastes in this example is an action verb.

So in short, there is no arbitrary list of how many linking verbs there are. There are, as Barrie England pointed out in the comment to the original question, 8 forms of the verb "to be", which is one linking verb.