Refering to this scene from Margin Call, where Will Emerson tries to convince Eric Dale to come back to the firm. In response Eric mentions that he built a bridge at his past job and goes on to provide a detailed calculation of the impact that it brought in the world.
12,100 people use the bridge everyday (both way). It saves 35 miles of extra driving each way. That amounts to 847,000 miles of driving everyday. Eric completed that project 22 years ago so over its life it comes down to 6,708,240,000 miles that haven’t had to be driven. Assuming driving speed to be 50 miles an hour that one bridge has saved the people 1531 years of their life!
1531 years of humanity saved! Isn’t that absolutely astonishing? That’s a contribution most people wouldn’t have in their life. This statistics should be told to people working in civil engineering. Undoubtedly, many professions have an immense yet often overlooked impact due to the indirect nature of their outcomes.
While professions like medicine or social work render visible impacts through lives saved or directly improved, countless others may not see the tangible outcomes of their toil. However, employing calculations similar to Eric’s can bring to light the profound and often unrecognized impact one’s work can have on the world.
Further Reading - Can one person make a difference (80000 Hours)