A law will make some precise quantitative prediction, "astrology" will make vague predictions like "A is correlated with B", or "A is positively correlated with

A law will make some precise quantitative prediction, "astrology" will make vague predictions like "A is correlated with B", or "A is positively correlated with B". Here is a spielraum[1] of possible experimental results, with the * indicating the region consistent with a law: 1) |------*------| Here it is for a vague speculation that there is "some correlation" (ie astrology): 2) |******-******| You can see it will be much easier to find evidence consistent with #2 than #1, even if there is nothing to the ideas at all. [1] Paul Meehl. 1990. Appraising and Amending Theories: The Strategy of Lakatosian Defense and Two Principles That Warrant It. Psychological Inquiry 1990, Vol. 1, No. 2, 108-141. http://rhowell.ba.ttu.edu/meehl1.pdf http://rhowell.ba.ttu.edu/meehl1.pdf [figure 3]