[airborne]

If there was more poverty before introducing the welfare system it might.

So it might not?

[A. Pole]

If there was more poverty before introducing the welfare system it might.

So it might not?

When A is accompanied by B and not A is accompanied by not B it is an indication of causal relationship, but not a proof. Especially in soft disciplines like economy, political science or sociology.

For example A and B might have common cause C, or relationship might be reversed.

For example more widespread education (C) might reduce poverty and induce society to introduce welfare system. Or more affluence can make welfare more affordable. (Third World countries do not have welfare because they are too poor to fund it).