The answer to the Ma nishtana
A young child asks about a number of strange changes we make at the Seder? We answer by explaining that “we were slaves to Pharoah in Egypt, and Hashem took us out from there”. But how does this explain why we make changes?
An ancient Yemenite commentary explains. A slave lacks choice, by doing things in an unusual way we manifest freedom. The essence of freedom is the freedom make choices, the freedom to do things differently. To be human is to have free will. Pharoah viewed his slaves as subhuman and therefore not having any ability to choose to serve God. At the Seder we take the opportunity to make this choice.