In an age in which no special premium was placed on experimental science St. Thomas did not feel the urge to submit the Christian life to a process of psycho-analysis. He was as convinced of the validity of reason, and the principles derived therefrom, as that the sense are to place us in touch with reality which would otherwise remain a blank to the human mind. In this sense he was an experimentalist, though his aim was not merely to classify phenomena and to place them under generalizations, but rather to deduce from them principles which in the light of reason would be valid at all times and under all circumstances. He believes in basing his conclusions on tested facts, and when it is a question of pure reason he is unwilling to draw conclusions in advance of the evidence. He is more than usually aware that an attitude of mind may be easily coloured by desires, but he is equally assured that under the influence of grace the desire of charity may give a deeper insight into divine truth by immediate intuition.

Through conscious or unconscious prejudices and preconceived attitudes of mind in matters pertaining to the spiritual life, the intellectualism of Thomism does not appeal to all, while many become wary of impending danger. Even those who might well be expected to know better, are afraid of the intimate connection which Dominicans hold to exist between speculative theology and contemplation. This doubtless is in some measure due to the marked contrast which is observed between the writings of St. Thomas and of those who are classified as mystical writers.