The mental model theory postulates that reasoners build models of situations described in premises. These models normally make explicit only what is true according to the premises. The theory has an unexpected consequence. It predicts the existence of illusions in inferences: Certain inferences should have compelling but erroneous conclusions. Previous studies have corroborated the existence of...

are familiar, indeed, with these effects, but there is something very remarkable in them. That ease should be procured by the juice of a poppy! that the wonderful mind should be influenced by a cause so apparently insignificant I The great John Hunter exclaimed, Thank God for opium! and it is an undoubted blessing that the Creator should have permitted such an antidote to the sufferings ot mank...

J . H . LEVY ,* W. AGENO,† N. C . CHAN,‡ M. CROWTHER ,§ P . VERHAMME ¶ and J . I . WE ITZ ,§ FOR THE SUBCOMMITTEE ON CONTROL OF ANT ICOAGULAT ION *Duke University School of Medicine, Durham, NC, USA; †University of Insubria, Varese, Italy; ‡Monash University, Clayton, Vic., Australia; §McMaster University and the Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada; and ¶Univ...

The application of the following new indices of the efficacy of antidotes has been substantiated and discussed: the "antidotal potency" as a ratio of LD50 of a poison when an antidote used to LD99 in control intact animals, and the "index of solid protection" as a ratio of LD10 in the experiments to LD90 in controls. The two indices are true for changing the lethality curve slope, which makes i...