Able Quote by Stephen Hawking
“One might think this means that imaginary numbers are just a mathematical game having nothing to do with the real world. From the viewpoint of positivist philosophy, however, one cannot determine what is real. All one can do is find which mathematical models describe the universe we live in. It turns out that a mathematical model involving imaginary time predicts not only effects we have already observed but also effects we have not been able to measure yet nevertheless believe in for other reasons. So what is real and what is imaginary? Is the distinction just in our minds?”
About This Quote
Source Book: A Brief History of Time, 1988
The quote argues that reality is defined by models that successfully predict phenomena, not by philosophical labels of “real” or “imaginary.”
In simple terms: Reality is what works, not what sounds real.
Key Takeaway
Focus on predictive power of models.
Themes
philosophy
science
ontology
epistemology
Mood
curious
thoughtful
inquisitive
Type
scientific
philosophical
reflective
When to use this quote
- physics research
- cosmology
- theoretical work
- educational lectures
Key Concepts
modeling
prediction
imaginary time
positivism
Questions to Reflect On
- How do we decide which models are “real”?
- Can something unobservable still be real?
A Different Perspective
Models may be useful even if their components seem abstract.
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