It's sort of a silly question, but it confuses me and I have no choice but to ask. What is the most accurate way to write: He came, he saw, he conquered. Is it OK to use 'and' as in 'and he conquered'; should there be a comma before 'and' as in: He came, he saw, and he conquered.
The original was written telegram style
a clipped way of writing that attempts to abbreviate words and pack as much information into the shortest possible number of words and or characters
For Caesar, this was easy because Latin basically does not use subject pronouns. The English sentence I came is rendered veni, the first person being communicated by the conjugation of the verb. Since Latin (unlike English) is a highly conjugated and declined language, much is communicated by the word endings and forms, allowing for a more concise rendition of concepts, and positioning of words is used primarily for emphasis or style, rather than grammatical structure.
In addition, Caesar omitted the et (English and) which was routinely used in Latin at the time, again to create a punchy style. He was describing a military campaign, so punchy seems appropriate.
There is no question that you could render this in numerous ways in English, depending on the emphasis and style you wished to apply.
John took on Rome. Came, saw, conquered.
He came. He saw. He conquered.
He came, he saw, and he conquered.
He came, saw, and conquered.
He came, and then he saw. Ultimately, he conquered.
All are correct (although the first relies on an implied subject). All are accurate. Which is appropriate (of these and the many other possible variants) depends on your personal goals and preferences.