Confusion understanding causality? I already know the simple definition that causal system is the one that does not depend on future values of input but today i was confused as i came across a new definition of causality after reading "signal processing first "about causality  as shown in attached snapshots

I have attached two pages snapshots and i have drawn a thin red line to left side of common para, para that occurs in both snapshots 

As shown in common para in  second line ,"cause does not precede corresponding effect" 

This statement is about causal filter but what does this statement means in simple words? 

Both snapshots contain a table ,upward snapshot contains table of non causal filter 

Bottom snapshot contains table of causal filter

We can see from table of causal filter that both input and start at same value of time (n=0)while table of non_causal filter shows that output starts at earlier value of time(n=-2) while input starts at a later value of time(n=0),thus
Indicating that output(effect)precede input(cause) in case of non-causal filter
The statement is not correct. In a causal system, the cause (i.e. input) does indeed precede (come before in time) the corresponding effect (output).

The correct statement is the cause doesn't follow the corresponding effect.

"Cause creates the effect", so in a causal system, Cause ($x[n]$) will always come first and then the corresponding effect ($y[n]$). 


  A causal $h[n]$ can not use samples $x[n+1], x[n+2], x[n+3], ...etc$ in order to create $y[n]$. $h[n]$ can only use $x[n], x[n-1], x[n-2],...etc$.