《徐霞客游记·滇游日记十二》
脊南面的路，又往深渊坠下去，我认为这里下去一定不会有大路，但道路却如此下坠，必定是因为有洞而开辟的。
脊南之路，复坠渊而下，以为此下必无通衢，而坠路若此，必因洞而辟。
The road on the south side of the ridge fell down to the deep valley, I thought maybe there wouldn’t be any pathway if I went down, but the road fell down like this, there must be a cave therefore the pathway was opened.
<s>[INST] Kindly elucidate the central themes in this passage in English: 脊南之路，复坠渊而下，以为此下必无通衢，而坠路若此，必因洞而辟。 [/INST] The road on the south side of the ridge fell down to the deep valley, I thought maybe there wouldn’t be any pathway if I went down, but the road fell down like this, there must be a cave therefore the pathway was opened.</s>
Kindly elucidate the central themes in this passage in English: 脊南之路，复坠渊而下，以为此下必无通衢，而坠路若此，必因洞而辟。
user
The road on the south side of the ridge fell down to the deep valley, I thought maybe there wouldn’t be any pathway if I went down, but the road fell down like this, there must be a cave therefore the pathway was opened.
assistant