Well, if that be true then further discussion is futile as we would be talking past each other.
Using this train of thought, everything we say is subjective as the definition of each word we use is not defined in Scripture, thus our discussion is a subjective malaise.
Example: You use the word "subjective" by that term is subjective as it "might be different from what you say it is. And you have no authority to claim your version or definition is any better or worse than a definition I might provide." Thus, all discussion if without meaning as, unless mathematics, it is 'subjective' (granted the meaning of subjective is subjective as are all words.)
Aside: To a point, you have a minor point. Language is subjective to a degree.
Unless you use the word SUBJECTIVE to define SUBJECTIVE,
you are violating the very belief in the doctrine by going outside of Scripture to define it. This is absurd.
Back to reality. I can define the term "sola scriptura" and you can define it. If we come to a common understanding we can then determine the validity of our posed definitions with the caveat that the english language is to a degree subjective.
Yes, my bad. I forgot to give that part of the definition of "scripture alone".
"Scripture alone" is the concept that the ONLY (and thus the word ALONE) infallible source of information about God is found in the 66 books of the Bible. It is a human concept and as you said "scripture alone" is therefore not without the possibility of error. You are an R.C. and you believe (IMO) that there are other infallible sources for God's communication. Like me, your idea is a human concept is therefore not without the possibility of error. Which gets us back to the difficult models use to determine the authority of scripture. Eventually we have to agree to disagree.
The phrase
sola scriptura is from the Latin:
sola having the idea of “alone,” “ground,” “base,” and the word
scriptura meaning “writings”—referring to the Scriptures.
Sola scriptura means that Scripture alone is authoritative for the faith and practice of the Christian. The Bible is complete, authoritative, and true. “All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness” (
2 Timothy 3:16). Gotquestions (I agree with this definition. My guess is the phrase became popular from those who wanted to differentiate themselves and their doctrine from the R.C. church in the reformation ... but I am not a historian).
Aside: the authority of the definition is man. In this case GOTQUESTIONS.ORG. For you and I the authority is anything we agree to with said authority limited to any discussion we have on the matter.