Following on from Mr Z's explanation from the American perspective, I'll give you a (much simpler) British English one: In GBE, we can use 'further' and for both physical and figurative distances. Taking the example above, we can say 'Marseilles is further from Paris than Bordeaux'. And we also use 'further' for figurative distances in the same way that AE does. In other words, we never need to use 'farther'! If you want an easy life, you can just follow the GBE model, use 'further' in all cases and forget about 'farther'. And if anyone tells you that 'further' is wrong, just tell them that you're a European and that you've learnt European/British English. Vive l'Europe! :) NB Just an additional question for Mr Z or any other native speakers of American English - Does ''Marseilles is further from Paris than Bordeaux' sound wrong to you? Does it sound like we're getting our grammar wrong when we Brits say this? :$

Hi Jérôme, In American English (the rules are different in this case from British English), we use "farther" for physical distance and "further" for metaphorical or figurative distance. Examples: "Marseilles is farther from Paris than Bordeaux." The distance between these three cities is obviously physical and measurable, so we use "farther." "Her students' progress in French is further along than anyone at the school expected." Here, the "distance" is the figurative distance between when students begin learning a language and when they become fluent. Since this distance can't really be physically measured, we use "further." I hope this helps. Please let me know if you have any more questions =)