If we imagine the levels of intelligence as a ladder with unevenly spaced rungs, there may be jumps that some intelligences are not able to complete, or their derivatives are not able to jump. So a type 3 mind may be able to jump up four levels of bootstrapping intelligence, but not five. Since I don't believe intelligence is linear (that is I believe intelligence grows in many dimensions), a better illustration may be to view the problem of bootstrapping super intelligence as navigating across a rugged evolutionary landscape.

The word 'greater' here is somewhat elusive. Can general intelligence be quantified? Or do we focus only on kinds of quantifiable intelligences?