At the beginning, we would like to point out that the mental abilities listed here are in many cases, recognized as science process skills.In other words, one can say: Science process skills are "practices". We can, simply, answer by confirming the fact that we cannot acquire these mental abilities without passing through practices and processes closely relevant to these abilities. On the following pages we demonstrate some mental abilities involved in practicing logical thinking. First: Recalling: Recalling is that mental ability which enables someone to retrieve information. In other words, an individual is required to remember what he studied or received before. This simple mental ability is a prerequisite for acquiring more complicated mental abilities. We should distinguish between two kinds of recall: ? The first what we can call it  "cheap recall" which aims at just communicating an idea to the learner  or to a colleague in a way that helps him to retrieve it literally when asked.Second : Comparing: Comparing represents one form of dynamic recalling to ideas, affairs and phenomena as the individual here practices many mental processes such as identifying similarities and differences among these ideas, affairs and phenomena.The merge of enriched recall and comparing represents the starting point for constructing the ability to produce new ideas and information, and practicing activities related to information processing.The second is enriched (fruitful) recall through which the individual can move on to build other higher mental abilities.These mental processes represents the essence of comparing as a mental process.In other words, the information learned beforehand can work as a base for acquiring more complicated abilities.This means that we can make connection between enriched recall and comparing.Then, we could question about the relationship between science process skills and mental abilities mentioned here.This kind of recall is value limited.?