One hundred and two university students were tested with two paper-and-pencil tests of speed of information processing and two paper-and-pencil IQ tests. One processing test measured speed of encoding alphanumerics; the other speed of encoding visual forms which varied in informational content from 0- to 3-bits. Hick's Law [linear relationship between reaction time (RT) and bits] was demonstrated psychometrically. At the more complex information processing levels, both processing tests correlated negatively with IQ and positively with each other. Processing tests with different knowledge bases are not uncorrelated as the “specificity of mind” view asserts (Ceci, 1990, Intelligence, 14, 141–150); rather they appear interchangeable as measures of IQ: the “singularity of mind” view is supported. For the simple processing tasks, RT correlated positively with IQ; a partial correlation analysis indicated that this was a consequence of the slowing of motor skills with age. The two IQ tests (the speeded Wonderlic and the power Shipley-Hartford) correlated to about the same extent with RT.