Stochastic: governed by probabilities. One cause may have different effects (with different probabilities)

One simplified example: if you put a ball on a table it will either stay put, roll but stay on the table, roll and fall off the table.
If you know nothing at all, all options will have equal probability. The more you know about the ball, the table, gravity, air current, ... the more precisely you will be able to predict what will happen. Since reality is almost infinitely complex, science assumes that you can never know all facts. Therefor 100% probability of prediction can not be reached. This means: no absolute right or wrong, no absolut truth can exist - simply because you can never know everything.