Actually, the advantage of science is that it can predict the future in an accurate fashion.
Ergo: I know x will happen because when all the variables are the same in the past, x has always happened.
The accuracy of the prediction is what changes in science, which is why it is a better system to use for predicting future events than other dogma based systems.
Ergo: Recently discovered factor y can be changed as a variable, and this accounts for x sometimes not happening the same way. We must account for this as a variable too.
Ergo: I know x will happen because when all the variables are the same in the past, x has always happened.
The accuracy of the prediction is what changes in science, which is why it is a better system to use for predicting future events than other dogma based systems.
Ergo: Recently discovered factor y can be changed as a variable, and this accounts for x sometimes not happening the same way. We must account for this as a variable too.