The comparative of 'forth,' from PIE *per- (forward) — it literally means 'more forward.'
To a greater distance or degree; additional; more. As a verb, to help the progress or development of something.
From Old English 'furþor' or 'furþur' (further, more forward), comparative form of 'fore' (before, in front), from Proto-Germanic *furþeraz, from PIE *pr- or *pro- meaning 'forward, before, in front of.' The PIE root *pro- is extraordinarily widespread: Latin 'pro' (for, forward, before), Sanskrit 'pra' (before, forward), Greek 'pro' (before, in front of), and Old English 'fore' and 'for.' The comparative degree was formed
The word 'further' is the comparative form of 'forth' — literally 'more forth.' The distinction between 'further' (degree) and 'farther' (physical distance) is a modern convention; historically they were used interchangeably. 'Forth' and 'first' share the same PIE root *per- (forward), making