The Ancient Romans already knew it

The Recently I read my Latin lesson notes (I studied the Latin language for two years). As you know, Latin was the language of the Roman Empire (about 500 BC – 400 AD) which, at its peak, was spread all around the Mediterranean Sea. Later, after the fall of the Roman Empire, Latin remained the language of the educated ranks and the Church in the Middle Ages. Today, Latin still remains the official language of the Christian Church in the Vatican City, Rome, Italy, EU. Latin influenced the vocabulary of all western languages,  so it is alive – in modified forms: mainly in Italian,  Spanish, Portuguese, French – and to a great extent also in English – as you may see for yourself when reading Latin sentences: many Latin words are easily comprehensible.

When I read the ancient Roman texts, I realise that there is a truth in them that people forget and then rediscover. It is known by different names: Psychology, Democracy, Sociology – but everything has already been put into words in the past.

To share the information, and to entertain you, I rewrote some Latin phrases.
In fact, I could adopt any of these citations as a 'conclusion'...
(Below each original sentence is my English 'translation'.)

TERRA COMMUNIS MATER OMNIUM MORTALIUM EST.
The Earth is the common mother of all mortal beings.

USUS EST MAGISTER OPTIMUS, ITAQUE SEMPER MEMORIAM EXERCETE!
Practice is the best teacher, therefore always exercise your memory!

PATRIA EST UBICUNQUE BENE.
The homeland is where it is good to live. 
(modern English expression: Home is where the heart is)

OMNIA MEA MECUM PORTO.
Everything that is mine I carry with me.

MESSE TENUS PROPRIA VIVE.
Live from your own harvest.

PROXIMUS SUM EGOMET MIHI.
I am closest to myself.

PROPRIA DOMUS OPTIMA.
Own house is the best.

LIBRI BONI SEMPER AMICI FIDI ERUNT.
Good books will always be loyal friends.

QUALIS LABOR TALE PRAEMIUM.
The reward is equal to the labour.

VOS VESTRAQUE FORTITER DEFENDITE!
Bravely defend yourself and everything yours!

DELIBERANDA SAEPE PERIT OCCASIO.
Opportunity is often lost by deliberation. (modern English: He who hesitates is lost)

OBLATAM TENE OCCASIONEM.
Take your chance.

NIL VOLENTI DIFICILE.
Nothing is difficult for the willing.

DEFICIT OMNE QUOD NASCITUR.
Everything that is born, dies.

PARCI NOSTRUM ET VESTRUM CENTUM ANNOS IMPLEBUNT.
Few of us nor you will live one hundred years.

SINE SPES VITA HOMINUM TRISTIS ESSET.
Human life would be sad without hope.

AGRI ET OPPIDA BELLIS DELENTUR.
Fields and towns are destroyed by war.

PACEM BELLO ANTEPONAMUS!
Let’s choose peace above war! (modern English: Make love, not war!)

PRAETERIA CORRIGI NON POSSUNT.
Past things can not be corrected.(modern English: It's no use crying over spilt milk)

AMEMUS PATRIAM, PAREAMUS LEGIBUS, POSTERITATIS GLORIAE SERVIAMUS.
Let’s love the homeland, obey the laws and serve the glory of posterity.

PATRIA LIBERA, CIVIBUS NIHIL CARIUS EST.
Nothing is dearer to citizens than a free homeland.

TRISTIS ERIS SI SOLUS ERIS.
You will be sad if you are alone. (Ovidius)

EGO DILIGAM TE, TU DILIGES ME.
I love you, you love me.

Conclusion (One more?): LEARN FROM THE PAST.
Without knowledge of the past, we are bound to repeat old mistakes.
(English expression:  History repeats itself.)

Some more Latin quotes with translations in my Czech blog.