What is the logic behind "I am X years old"?

Question

In most languages (I know of), people say their age with a construction like "I have X years". In English, however, you say how old you are instead. So I'm curious about what is it about the logic of English that makes this sound more natural than "I have X years". All I can find is that "this is just cultural/this is just how the language evolved", but I'm sure there's some logic to it.

I'm also particularly interested in the logic that makes the construction "I am X years old" possible. I suppose it comes from the fact that, in English, we modify/specify words by placing words before the word we want to modify/specify. Something like:

— I am old.
— How old?
— Very old.
— How old exactly?
— 900 years old.

Am I on the right track? Is "900 years" in this case really behaving the same as "very", or interchangeable with it? (The available information about numerals as adjectives or adverbs is very conflicting.) Or is there something more specific about numbers, or this particular construction, that applies here?

Answer 1

Here's a much closer model:

How tall is it? It's 50 metres tall.

How long is it? It's two miles long.

How long is it? It's 40 minutes long.

How old are you? I'm 31 years old.

This doesn't work for all adjectives, only ones of dimension. Even other easily quantifiable ones are different:

How hot is it? It's 30 degrees hot.

How bright is it? It's 60 Watts bright.

So we might say that age is conceptualized as a kind of dimension.

(That said, as I noted below, in comparatives this pattern seems to open up to more types of adjective: It's 60 pounds heavy works as expected, but we do use it in It's 60 pounds heavier than that one — and same for brighter, hotter, cleaner, etc.)

By the by, to us the idea of "having" years sounds odd. Where do you keep them? In the attic? :p

Answer 2

There is no logic. In fact English used to be a language where you could use either be or have to express specific ages:

[I]n Latin we find sum, esse, fui 'be' to express age (see fuit in (19)), whereas in Italian, which is a descendant of Latin, only AVERE 'have' is used, e.g. ho trenta anni (I-have thirty years) 'I'm thirty years old'. No wonder that English has enjoyed a similar competition; in Middle English not infrequently the structure with HAVEN is attested, consider:

• (20) a. Þet knaue child for-tene ger Schel habbe.
  that male child fourteen years shall have c1350 (a1333) Shoreham Poems (Add 17376) 61/1726
• b. Thou hast not git fifty geer, and hast thou seyn Abraham?
  KJV: 'Thou art not yet fifty years old, and hast thou seen Abraham?' (c1384) WBible(1) (Dc 369(2)) John 8.57
• c. þe hors schulde haue xxti winter.
  the horse should have twenty years (c1443) Pecock Rule (Mrg M 519) 268

(Grammaticalisation Paths of Have in English)

Going back to modern English, every year you get older and have another year under your belt. Hardcore criminals do dozens of years and people who are dying may only have a few months. (Note: "have another year under your belt" means to be another year older, especially in the sense that you've experienced another year's worth of life; "do X months/years" means to spend that amount of time in prison; "have X months/years" means that doctors only expect you to live that much longer.)

The fact that in other, superficially similar expressions we use be is a mere coincidence. It may be idiomatic to say that the paper is millimeters thick, but it's also idiomatic to say that the paper doesn't have enough thickness.

Have and be are both verbs that are used very arbitrarily. (And you can see how arbitrary it really is by looking at the Middle English Dictionary's other definitions for have that have fallen out of fashion. You don't say that you "have right" anymore, for example: you are right.)

Answer 3

Note that there is at least one context in which one can have years in English: when they are years of something. (Laurel already brought up another, different sense.) For example, someone can “have ten years of experience.” or “fifty years of marriage,” in the same way that we can have twenty minutes of running, an hour of music, or sixteen hectares of farmland.

This can mean that some task lasted for that length of time. It can also mean that something accumulated over that length of time. The latter can also be phrased, “years’ worth of ....”

Answer 4

This fits a general pattern

Rather than being specific to the concept of age, this usage follows a general pattern in English in which adjectives / qualities of a noun are often expressed as 'states of being' when in a Romance language they would often be expressed as qualities that the noun 'has' or possesses.

Some examples comparing English and Spanish (where 'to have' is the verb tener):

I am twenty-six. / Yo tengo viente seis. [I have 26.]

Are you hungry? / Tienes hambre? [Do you have hunger?]

He is thirsty. / El tiene sed. [He has thirst.]

She is hot. / Ella tiene calor. [She has heat.]

We are sleepy. / Nosotros tenemos sueño. [We have sleepiness.]

They are skilled. / Ellos tienen habilidades. [They have abilities.]

As to why the general pattern is this, that is a much deeper question that other answers have addressed in terms of the historical development of the languages. Suffice to say, it is not specific to the concept of age.

Answer 5

Incuriously, all you could find was "this is just cultural/ how the language evolved" because that's all there is to it: this is about the nature of language, not logic.

The French say "I have Y years” because theirs is a Romance language, based on Latin. The English use “I am Y years old” because like modern German, theirs is anciently a Germanic tongue…

Volumes have been written on the differences and they are for degree-level study, not SE forums.

The very words “language” and “tongue” are, respectively, Romance and Germanic and while many of us know they are almost perfectly synonymous, at the same time all of us know they are very, very different.

Since both seem to matter what’s your own native tongue, please? Will you say which “most” languages you know of, or Edit the Question to leave that out?

No logic is needed to make the construction "I am X years old" possible. If it was, no such idea could ever come from “the fact that, in English, we modify/specify words by placing words before the word we want to modify/specify” for the simple reason that that’s not true; we might sometimes, but never necessarily.

Ignoring any idea of “logic” will you please consider the very different example of a person walking towards a door?

English speakers say simply “I approach the door.”

French speakers say “I approach myself to the door.” (“je m'approche (de) la porte…”

Exact translation might never be possible, precisely because the languages do not work the same way; do not follow the same “logic”

Native English speakers never "say…" their age. They either "state…" their age, or "say that their age is…" Does that difference matter, or help?

More purely Germanic languages do, and to an extent ancient English did insist but modern English has no real interest in word order. There is no reason for modern English to choose "That was done well" over "That was well done" whatever anywhen German, ancient Latin or modern French suggest.

What track you’re on isn’t clear but in your example "900 years old” might well “behave”, though it could too rarely “be behaving” in the same way as "very old” in English, and then not generally but only in particular circumstances.

What information you’ve found about numerals as adjectives or adverbs might be as conflicting as possible and to that extent, it necessarily is nothing like “the available information…” Sorry.

Nothing more specific about numbers, or this particular construction, applies here and still, all you could find was "this is just cultural/ how the language evolved" because that’s all there is to it: this is about the nature of language, not logic.

Answer 6

In Italian, which like Spanish is a Romance language, if you want to ask someone their age you will typically ask:

Quanti anni hai / ha?

Which translated, literally, is

“How many years have you got?”
“How many years do you have?”

But there is also the alternative

“Ma quanto sei vecchio/a!?” “But how old you are!?”

It suggests the person being asked is very advanced in their years. It can be said teasingly, as a criticism,or to express incredulity. As an example, I found this headline

“Tartaruga, quanto sei vecchia?” “Tortoise/turtle how old are you?”

I don't know if Spanish has the same usage, but asking how old a bridge, building or painting is not that unusual in Italian. “Sono di Genova. Allora me lo dice quanto è vecchio questo orologio?” “I'm from Genoa. So, are you going to tell me how old this watch is?”

In English, people don't imagine owning years as they do with privileges, objects, and possessions. Instead, the question “How old are you?” is primarily focused on the idea of people aging (getting older) not in the number of years they possess.