The rule in one line
Thou is the subject. Thee is the object. That is the entire distinction, and it is exactly the same one you already apply without thinking between I and me, he and him, she and her, we and us.
Thou lovest her. She loves thee. Not the other way round, and never both ways in the same breath.
| Function | Form | Modern equivalent | Example |
|---|---|---|---|
| Subject | thou | you (subject) | Thou art late. |
| Object | thee | you (object) | I saw thee. |
| Possessive determiner | thy | your | Thy hand. |
| Possessive determiner before a vowel | thine | your | Thine eyes. |
| Possessive pronoun | thine | yours | The fault is thine. |
| Reflexive | thyself | yourself | Know thyself. |
Thy and thine split on sound, not on meaning, exactly as a and an do: thy hand but thine arm. Standing alone at the end of a clause it is always thine.
Why 'thee' in a subject slot is so conspicuous
Because it is the same error as 'me went to the shop'. Anyone with an ear for English will flag it instantly, even if they could not name the rule or say which century the word belongs to.
This is why it is worth getting right in a translator rather than treating thou and thee as decorative variants to alternate for texture. Substituting one archaic-sounding word for another produces something that reads as costume rather than as language, and the failure is visible to a very large number of readers — the paradigm survives in the King James Bible, in Shakespeare, in hymns, and in the dialect of parts of northern England, so a great many people have absorbed it without study.
It is also, conveniently, a rule a program can apply properly. Determining whether a pronoun is a subject or an object is a matter of what it attaches to, and that is tractable enough to do correctly rather than approximately.
The verb has to agree
Thou takes its own verb endings, and this is the part most often dropped. A sentence with thou and a modern verb form is only half converted.
The regular ending is -est: thou walkest, thou knowest, thou givest. In the past tense it is often -edst: thou walkedst.
| Verb | With thou | Modern |
|---|---|---|
| be (present) | thou art | you are |
| be (past) | thou wast / thou wert | you were |
| have | thou hast | you have |
| do | thou dost | you do |
| will | thou wilt | you will |
| shall | thou shalt | you shall |
| can | thou canst | you can |
| say | thou sayest | you say |
| go | thou goest | you go |
The third person of the same period takes -eth rather than -est: he walketh, she hath, it doth. Attaching -eth to thou is a common and very audible mistake — thou walketh is wrong in the same way as 'you walks'.
Thou was not the polite form
A persistent misunderstanding is that thou is formal or reverent, presumably because most people meet it in scripture. It was the opposite.
English worked like French and German still do. Thou was singular and familiar — used to one person you knew well, to a child, to a servant, or to someone you considered beneath you. Ye and you were plural, and also the respectful singular used to a superior or a stranger.
So the choice carried social weight. Switching to thou mid-conversation could be intimacy or it could be a deliberate insult, and Elizabethan drama uses that shift on purpose. It is the point of several exchanges in Shakespeare, and it is invisible to a modern reader who assumes thou simply means 'you, but older'.
The reason thou survives in religious language is a historical accident of the reverse kind: it was the form for addressing one person directly and intimately, which is precisely what prayer is. By the time thou had disappeared from ordinary speech the liturgical language had frozen, and the archaic form acquired a formality it never originally had.
What a translator can and cannot do with this
Modern English lost the distinction entirely, so translating in this direction means recovering information the source text does not contain. 'You' might be one person or several, familiar or formal, and a program cannot always tell.
Where the number is recoverable from context — a verb form, a following noun, an explicit plural — the right form can be chosen. Where it is not, something has to be assumed, and assuming singular familiar produces the effect most people are after.
What the translator does do reliably is get the case right, keep the verb agreeing with its subject, and choose thy or thine by the sound of the following word. Those are the three things that separate a passable imitation from an obviously wrong one, and all three are mechanical.
It converts the pronoun system and the verb endings. It does not convert vocabulary wholesale into Early Modern English, which would need a period dictionary and would produce something no more readable than the original.
Where this comes from
- The paradigm and verb endings described here are the standard account of Early Modern English second-person forms found in historical grammars of English.
- The social distinction between thou and you is well documented in studies of Shakespearean and Early Modern usage, though individual instances in literary texts are often open to interpretation.