The taxonomy of human mental abilities should answer questions: “Which mental abilities exist in reality?”, “How many mental abilities exist?” and “How can we classify mental abilities in a logical system (What are the relations among them)?”.

We can find the basis for a taxonomy in a theory of intelligence, described in the previous chapter. There the modular structure is described and the process model of intellect is shown.

Intelligence is only one ability. It is a basis for the effectiveness of each mental module. Due to the specialization of mental functions research reveals a small number of broad abilities clusters and within them several primary mental abilities. The consensus of which these abilities are and how many they are, has not been reached yet. The list below, shows mental abilities, which are by research, done in the world, best confirmed.

PERCEPTUAL ABILITIES

The broad visual factor:

perceptual speed
closure speed
flexibility of closure
spatial ability

The broad auditive factor:

discrimination among sound patterns
maintaining and judging rhythm
speech perception under distraction/distortion

CENTRAL PROCESSING AND WORKING MEMORY

memory span
mental manipulation (temporal tracking)
(inductive) reasoning

MEMORIZING

associative memory
memorizing meaningful material

DIVERGENT RETRIEVAL

word fluency
ideational fluency
flexibility
originality

EXPERIENTIAL ABILITIES

verbal ability
numerical ability
mechanical ability
syllogistic reasoning

PSYCHOMOTOR ABILITIES

oculomotor coordination
finger and manual dexterity

Concerning relations among mental abilities, it holds true:

• All correlations among primary mental abilities are positive.
• Correlations among primary mental abilities within a broad cluster are higher than correlations among primary mental abilities from different clusters.