"Therefore . . ." - Crossword Clue, Answer and Explanation

'therefore' is the definition.
(I know that therefore can be written as hence)

This is all the clue.

(Other definitions for hence that I've seen before include "Therefore, consequently" , "From this place or time" , "From this time, or for this reason" , "As a consequence" , "Thus" .)

I've seen this clue in the USA Today, the Sydney Morning Herald, The Mirror, The Star Tribune, The Guardian, The Wall Street Journal, The Telegraph, the Evening Standard, the Newsday, the Universal, The Times, The Independent, the Penny Press, the King Feature Syndicate and the LA Times.

'therefore' is the definition.
(I've seen this before)

This is the entire clue.

(Other definitions for ergo that I've seen before include "Thus" , "Consequently" , "'Cogito, ---- sum'" , "so philosopher wrote in Latin" , "It follows" .)

I've seen this clue in the Sydney Morning Herald, The Star Tribune, the Newsday.com, the Newsday, the Penny Press, the King Feature Syndicate, The Mirror, The Telegraph, the Evening Standard, the Universal, The Times, The Independent, the LA Times, the USA Today, The New York Times, The Sun, The Guardian, The Wall Street Journal and The Washington Post.

'therefore' is the definition.
('so' can mean 'consequently' or 'therefore')

This is all the clue.

I've seen this clue in the King Feature Syndicate.

"Therefore . . ." (5)