Id certum est quod certum reddi potest - That is certain that can be made certain

Id imperfectum manet dum confectum erit - It ain't over until it's over

Id tibi praebet speciem lepidissimam! - It looks great on you!

Ille dolet vere, qui sine teste dolet - He mourns honestly who mourns without witnesses. (Martialis)

Illegitimis nil carborundum - Don't let the bastards grind you down

Illiud Latine dici non potest - You can't say that in Latin

Illius me paenitet, dux - Sorry about that, chief

Imitatores, servum pecus! - Imitators, you slavish crowd! (Horace)

Imperium et libertas - Empire and liberty. (Cicero)

Impossibilium nulla obligatio est - Nobody has any obligation to the impossible. (Corpus Iuris Civilis)

In absentia - In one's absence

In aere aedificare - Build (castles) in the air. (St. Augustine)

In alio pediculum, in te ricinum non vides - You see a louse on someone else, but not a tick on yourself. (Petronius)

In dentibus anticis frustrum magnum spiniciae habes - You have a big piece of spinach in your front teeth

In dubiis non est agendum - In dubious cases, you should not act

In his ordo est ordinem non servare - In this case the only rule is not obeying any rules

In hoc signo vinces - In this sign, you will be victorious. (Eusebios)

In libris libertas - In books (there is) freedom

In magnis et voluisse sat est - To once have wanted is enough in great deeds. (Propertius)

In medio tutissimus ibis - In the middle of things you will go most safe. (Ovid)

In omnia paratus - Prepared for all things

In pari materia - Of like kind

In posterum - Till the next day

In quaestione versare - To be under investigation

In silvam ne ligna feras - Don't carry logs into the forest. (Horace)

In spiritu et veritate - In spirit and truth. (Versio Vulgata)

In vinculis etiam audax - In chains yet still bold (free)

In virtute sunt multi ascensus - In excellence there are many degrees. (Cicero)

Indulgentiam quaeso - I ask your indulgence

infra dignitatem - Undignified (beneath (our) dignity)

Inhumanitas omni aetate molesta est. - Inhumanity is harmful in every age. (Cicero)

Iniqua nunquam regna perpetuo manent - Stern masters do not reign long. (Seneca Philosophus)

Iniuria non excusat iniuriam - One wrong does not justify another

Intellectum valde amat - Love the intellect strongly. (St. Augustine)

Intelligenti pauca - Few words suffice for he who understands

Intelligo me intelligere - I understand that I understand. (St. Augustine)

Inter nos - Between us

Inter vivos - Living

Interfice errorem, diligere errantem - Kill the sin, love the sinner. (St. Augustine)

Inventas vitam iuvat excoluisse per artes - Let us improve life through science and art. (Vergil)

Ipsa scientia potestas est - Knowledge itself is power. (Bacon)

Ipse dixit - He himself said it. (Cicero)

Ira furor brevis est - Anger is a brief insanity. (Horace)

Isso fede - This stinks

Ita erat quando hic adveni - It was that way when I got here

Iustita omnibus - Justice for all