yin1 means 'cause'


yin1 has the following two components . The first component denotes an enclosed space and the second component is the character da meaning 'big man'. When a big man is shut up in a small cubicle, he will never remain passive because he is a grown-up person and not a passive baby. Something is bound to happen thus the concept of 'cause'.

yuan2yin1 means 'reason' and literally translates as 'origin'-'cause'.

yuan2 is composed of  where the first component is a graphical representation of a 'precipice' and the second component denotes 'water spring'. Water flows from the top and therefore the concept of 'origin'.

yin1guo3 means 'cause and effect' and literally translates as 'cause'-'fruit'.

guo3 is from the script  which shows something on top of a tree and hence denotes 'fruit'. Other extensions of guo3 are 'result' and 'consequence'.