I never met Carl Sagan. I've read his materials (both technical and popular) and listened to his talks. Dr. Sagan was a fierce questioner of many things. But in that questioning process is a framework for which answers can be discovered. Here are two nice quotes
The conjecture there is cause and effect without confirming cause and effect is another common naive thought process. We get that from the anti-vaccine, global warming deniers to name a few. We also get this from those who conjecture that estimates are the smell of dysfunction without every stating the dysfunctions, discovering the cause and effect connections for the dysfunction (the unstated dysfunction).
Dr. Sagan primary message was and still is ...
I don't want to believe, I want to Know
If we seek to improve the probability of success for our software intensive systems, we can't just believe the unsubstantiated conjecture of a group of unhappy developers tired of being abused by bad managers. We need tangible evidence that their conjectures are not only testable outside their personal anecdotes, but also those conjectures are not violations of the basis of all business decision making.
And just for the record.
- Estimating is hard, so are many things. That does not remove the need to estimate when making decisions in the presence of uncertainty.
- Estimates are misused by bad managers and even well-intentioned managers. That does not remove their need when making non-trivial business and technical decisions. By non-trivial I mean value at risk is at a level that unfavorably impacts the business when the decision turns out to be wrong.
- All project work is probabilistic with an uncertainty of the future outcomes. Making decisions requires making estimates
- Assessing value requires we know the cost to achieve that value. Since but value and cost are probabilistic, no assessment of value can take place without estimating both cost and value. This is the basis of Microeconomics of business management.
A final thought about unsubstantiated opinions, masking as personal anecdotes (thanks for this Peter)