Two Levels of the Mass-Count Distinctions and Noun Classifications in English and Japanese

Why are items such as furniture, cutlery, and jewellery considered mass nouns, even though we can readily count the number of pieces of furniture, knives and spoons, and jewels? Many English learners have thought of this question at least once. The purpose of this paper is to contribute to a study of nominal architecture in languages. To achieve this long-term goal, this paper aims to formally answer the above-mentioned question.
It is well-documented but has not been widely analyzed why and how furniture is somewhat countable but somewhat mass. We propose two levels of the mass-count distinction: conceptual and syntactic, to capture the discrepancy between the behaviours of furniture and the mass-count distinction.
Furthermore, we present detailed classifications at the conceptual levels, drawing from impressionistic tests and linguistic tests that incorporate counting and measuring. A close scrutiny reveals that a simple dichotomy (e.g., countable, uncountable) cannot capture the masscount distinction at the conceptual level. Instead, this paper proposes four-way distinctions at the conceptual level: countable, uncountable, flexible, and ambiguous.
Moreover, this paper examines crosslinguistic variations of the classifications in terms of the conceptual mass-count distinction. Whereas English has four groups of nouns, Japanese has only three groups, including uncountable, flexible, and ambiguous. Literature has examined the syntactic mass-count distinction in Japanese, but it has not focused on the conceptual mass-count distinction and its classification in Japanese. This paper fills that gap. Especially, this paper offers novel evidence to show that count-y nouns in Japanese, including human nouns, can be uncountable contextually.