Abstract: A method of promoting fluid intelligence abilities in a subject includes the steps of: selecting one or more serial order of symbols sequences from a predefined library of complete symbols sequences and, from this selection, providing the subject with one or more incomplete serial orders of symbols sequences; prompting the subject to manipulate symbols within the one or more incomplete serial orders of symbols sequences or to discriminate differences or sameness between two or more of the incomplete serial orders of symbols sequences; determining whether the subject correctly manipulated the symbols or correctly discriminated differences or sameness between the two or more further selected incomplete serial orders of symbols sequences; if the subject correctly manipulated the symbols or correctly discriminated differences or sameness between the two or more of the incomplete serial orders of symbols sequences, then displaying the correct manipulations or discriminated differences or sameness with at least one