Shulchan Aruch (Code of Jewish Law, Siman 473, Section 4): "If one ate matzah without intent, such as if non-Jews or bandits forced him to eat it, he has fulfilled his obligation, since he knows it is Passover night and he is obligated to eat matzah. But if he thinks it is a weekday or that it is not matzah, he has not fulfilled his obligation."

And the Beur Halacha commentary states: "Refer to the Chak Yaakov's opinion that even in the case of bitter herbs, if one did not know it was bitter herbs or thought it was a weekday, he still fulfills his obligation. His main opinion is that a Rabbinic commandment does not require intent. According to what we wrote above (Siman 60, S"K 10) in the name of several poskim, one should not differentiate in this matter, so it is the same with bitter herbs."

And there it is written: "The Magen Avraham, quoting the Radvaz, wrote that this applies specifically to a biblical commandment, but for a Rabbinic commandment, intent is not necessary. According to this, with all blessings, which are also Rabbinic, except for the blessing after meals, if one did not have intent, he has fulfilled his obligation retroactively. However, in several places in the Shulchan Aruch, it seems that there is a distinction, and similarly, from the commentary of the Gra in Siman 589 (Sections 3-4), it also seems that one should not differentiate between a biblical commandment and a Rabbinic commandment." The meaning of bitter herbs is explained in the Mishnah (Pesachim 16b), that we eat the bitter herbs to remember how the Egyptians embittered the lives of our ancestors in Egypt.