For most of the twentieth century, gasoline engines relied on carburetors to mix air and fuel because they were simple, durable, and inexpensive to produce. Fuel injection had existed much earlier, appearing in aircraft engines in the 1930s and in a small number of high performance or racing cars in the 1950s, but it was too complex and costly for mass-market use. The major shift began in the late 1970s and continued through the 1980s as governments introduced stricter emissions standards, fuel prices rose, and electronics became reliable and affordable. By the early 1990s, electronic fuel injection paired with oxygen sensors had largely replaced carburetors in passenger vehicles, marking a move from mechanically preset engines to systems that could measure combustion, adapt to conditions, and continuously correct themselves.

A carburetor works a bit like a fixed recipe. It mixes air and fuel using simple mechanical parts, based on how much you press the gas pedal and how fast air is flowing into the engine. Once it’s set, it mostly assumes everything is working as expected. If the weather changes, you drive up a mountain, or the engine gets older, the carburetor doesn’t really “notice.” To stay safe, it usually adds a little extra fuel, which keeps the engine running but wastes fuel and creates more pollution.

Fuel injection with an oxygen sensor works more like a smart system that checks its own results. Instead of guessing, the engine constantly measures what actually happened during combustion by sensing how much oxygen is left in the exhaust. A small computer then adjusts the fuel in real time to get the mixture just right. This means the car can adapt automatically to heat, cold, altitude, or engine wear, using less fuel and producing fewer emissions. In simple terms, carburetors rely on assumptions, while fuel injection listens, learns, and corrects itself as it goes.

In this week’s Torah reading of Vayigash (Genesis 44-47), Judah’s decision to step forward and speak directly to Joseph marks a similar shift, from acting on assumptions and distance to engaging with reality through direct feedback and responsibility.

Last week we saw Joseph, the Viceroy of Egypt, play out his charade of accusing his brothers, who didn’t recognize him, of being spies. They had simply come to Egypt from nearby Canaan to get food during the famine that Joseph had correctly predicted. The ruse continued when Joseph had his silver goblet planted in Benjamin’s satchel. When Benjamin was caught with the “stolen” goblet, Joseph decreed that Benjamin would become his slave while the other brothers were free to return to Canaan.

The brothers understood that if that were to happen, the news would likely kill their elderly father, Jacob. This is where Judah steps forward.

He approaches Joseph, repeating the history from his perspective, explaining their innocence. However, he takes one step further. He tells Joseph of Benjamin’s special relationship with Jacob, as he is the only surviving son of Jacob’s preferred and deceased wife, Rachel. In one of the greatest ironies in the Bible, Judah tells the unrecognized Joseph how Joseph had died, when Judah was actually the person responsible for selling him into slavery!

Judah states that he had guaranteed Benjamin’s safety to Jacob and he couldn’t face his father without Benjamin. Judah offers himself as a slave to Joseph in Benjamin’s place.

This is where Joseph breaks down and the whole charade comes apart. Joseph orders everyone except for the brothers to leave the room. He cries out and states “I am Joseph!”

The brothers are shocked into silence. Joseph continues to tell them how the famine which has run for two years will continue for another five. Furthermore, he doesn’t hold the brothers’ action of selling him into slavery against them. Instead, he attributes it directly to God as part of God’s plan to put him in charge of Egypt during the famine in order to save Jacob, his brothers and the entire family. He says that he will support the family and to quickly bring Jacob and everybody else down to Egypt.

Joseph and Benjamin cry on each other’s shoulders. Joseph subsequently kisses and cries on the shoulders of each of his other brothers. Then the brothers speak with Joseph.

The news of Joseph’s brothers’ arrival causes a commotion and is welcomed by Pharaoh and his advisors. Pharaoh invites Joseph’s family to emigrate to Egypt, and he offers them the best land in the country.

Jacob and family indeed descend to Egypt. We’re told that Jacob’s family is composed of 70 souls. Jacob and Joseph are reunited after Jacob thought his favorite son was dead. Joseph presents five of his brothers to Pharaoh. Pharaoh offers them jobs, but they politely state that they’re simple shepherds. Then Pharaoh and Jacob meet. Jacob blesses Pharoah. Pharaoh asks Jacob how old he is. Jacob says he’s 130 years old and that they’ve been few and bad years and didn’t reach the years that his ancestors lived (his father Isaac lived until 180 and grandpa Abraham until 175).

The narrative then takes a break to tell us about Joseph’s economic management of Egypt on Pharaoh’s behalf during the famine. The first thing to run out was the money. The Egyptians and Canaanites spent everything they had on the grain Joseph had in store. Next, Joseph gathered all the livestock which they traded for food. When they had nothing else left, the people offered to sell themselves and their land to Pharaoh. Joseph, now the administrator of all the land (except for the Egyptian priests’ land) moved the entire population around, probably reinforcing that the people were no longer landowners.

He then gave all this population of indentured slaves seeds to plant, telling them they can keep 4/5ths of the produce and 1/5th they would need to give to Pharaoh. This may be the first documented national tax in history – 20% — not bad!

The reading ends by telling us that Israel (the other name for Jacob and family) settled in Egypt in the region called Goshen, took possession of it, grew and multiplied greatly.