Garbage In, Garbage Out
Charles Babbage, the man usually known as "the father of the computer", was once asked a form of this question:
"If you put the wrong numbers in the computer, will you still get the right answer?"
This question seems absurd to us. Imagine how nonplussed Babbage - who knew the machine inside and out - must have felt.
"I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question," Babbage said.
In modern English:
"Dude, what are you talking about?"
The concept behind this question came to be coined in the computer science world as "Garbage In, Garbage Out."
In the case of my former programming professor, the phrase probably should have been "Garbage In, The Whole Office Is Flooded With Tens of Thousands of Printed Pages Containing Meaningless Figures Because Someone Forgot to Close The Loop In His Code."
That's another story for another time.
Since computers are modeled from human logic, we are similar to them. For the most part, we are what we absorb. We can use our social cues to filter ourselves (well, some of us can), but our thoughts and beliefs and speech are mostly influenced by environment. This is a theme in one-liners that stand the test of time.
"You are what you eat."
"You will be the same person in five years as you are today except for the people you meet and the books you read."
"You are the equivalent of the five people you spend the most time with."
We also see hints of Garbage In, Garbage Out in The Hero's Journey. Once an inciting incident motivates our main character to change his path, his still needs a guide to lead the way. Without new input in the form of Obi-Wan Kenobi, Luke Skywalker is forever complaining about the farm, staring at the sky, and drinking that weird blue milk.
Moment to moment, this input/output dynamic takes the form of the recency effect. Reading the word "kerfuffle" in a novel minutes before you sit down to write a blog post makes it all the more likely that “kerfuffle” will worm its way into your brain and on the page.
This is probably why Stephen King spends half his day writing, but the other half is spent reading.
It's also probably why, after spending the whole week in my house alone with old books and words, I left the house, looked in the face of a person selling me Girl Scout cookies and said:
"I'd never begrudge you a Do-si-do, my good man!"