Birds of a feather flock together. The tendency to judge an aphorism or saying as more truthful merely because it rhymes.
Free will, eh? The idea that one stimulus can trigger the recall (or facilitate more rapid recall) of another.
It exists – so it must be good. No really, this is a bias. Occurs when we treat the mere existence of something as evidence of its goodness. People often tend to prefer concepts or ideas that already exist, or are easy to conceive, over concepts that have not been implemented or are counterintuitive.
Good, better, best! The idea that we can be pushed to choose one of several options more reliably through the introduction of an option that is inferior to the desired option in every way.
This is also known as the decoy effect: a decision between two roughly equal options can be tipped towards one of the options by adding a third, ‘decoy’ option that dominates one of the original options.