The conspiracy speech of Joseph's brothers, preserved in Targum Pseudo-Jonathan on (Genesis 37:20), ends with a sentence that is, in its own dark way, one of the most revealing lines in Genesis. We shall see what will be the interpretation of his dreams.
Read it again. The brothers are not denying that Joseph has dreams. They are not even denying that the dreams might be prophetic. They are saying: let us kill the dreamer, and then we will find out what the dream actually meant. If the dream was true, it cannot survive his death. If the dream was false, it dies with him anyway. Either way, the experiment is clean.
The sages caught the flaw in this logic immediately. A true dream from God does not depend on the dreamer's survival for its fulfillment. If God has decreed that Joseph will rise, killing Joseph will only reroute the prophecy. The brothers thought they were testing the dream. They were actually making it true. It is because they threw him in the pit that he ended up in Egypt. It is because he ended up in Egypt that they eventually bowed before him, hungry and begging for grain.
The Talmud teaches in Berakhot 55b that a dream's meaning follows its interpretation. The brothers gave Joseph's dream the only interpretation available: they enacted it. Their violence became the vehicle of his rise.
God's plans, the Targum is teaching us, are not fragile. You can throw them into a pit and they will still walk out wearing robes of state.