The mail on Jim Manzi’s “The Right Formula” is piling up, but before letting it fly, it would probably be helpful to define our terms. In the piece, Manzi writes:
Scientific finding X implies liberal political or moral conclusion Y. Important contemporary examples include the assertions that evolution implies atheism, and the fact that CO2 is a greenhouse gas implies that we must reduce carbon emissions rapidly and aggressively.
The “scientific finding” is that “CO2 is a greenhouse gas.” Since some correspondents are interpreting this as a broad acceptance of the AGW agenda, I have asked Jim to define X, and I expect his answer will be something like “Increased atmospheric CO2 will lead to higher temperatures (all things being equal).”
A reader offers four related facts instead:
An important question is: when are we arguing the science?
There are established scientific facts, there are hypotheses developed to be the basis of experiments based on those facts, and finally there are conclusions based on the results of repeated and repeatable experiments.
When Al Gore says that “science has shown” that Florida will be underwater if we do not radically restrict CO2 emissions, he confuses settled science with a hypothesis.
Science may show:
1. Global average temperatures are rising.
2. CO2 is accumulating in the atmosphere.
3. Human activities are contributing to that accumulation.
4. CO2 is a greenhouse gas which retains heat.
Once you get beyond these basic facts, you are entering the realm of hypothesis. The science has not shown that Florida will be underwater. The hypothesis is that increased concentrations of CO2 may cause a corresponding increase in global average temperatures – which, left unchecked, will cause a catastrophic change in the Earth’s climate leading to rising sea levels.
The purpose of developing a hypothesis is to clarify the design of the experiments that will be used to test the hypothesis. Where Al Gore goes off the tracks is that he mistakes the hypothesis for the conclusion of an experiment that has established the validity of a hypothesis.