I. Philosophical and Scientific Thought -- II. A Psycho-physiological Consideration -- III. Memory. Reproduction and Association -- IV. Reflex, Instinct, Will, Ego -- V. Development of Individuality in a Natural and Cultural Habitat -- VI. The Exuberance of the Imagination -- VII. Knowledge and Error -- VIII. The Concept -- IX. Sensation, Intuition, Phantasy -- X. Adaptation of Thoughts to Facts and to Each Other -- XI. On Thought Experiments -- XII. Physical Experiment and its Leading Features -- XIII. Similarity and Analogy as a Leading Feature of Enquiry -- XIV. Hypothesis -- XV. Problems -- XVI. Presuppositions of Enquiry -- XVII. Pathways of Enquiry -- XVIII. Deduction and Induction Psychologically Viewed -- XIX. Number and Measure -- XX. Physiological Space in Contrast with Metrical Space -- XXI. On the Psychology and Natural Development of Geometry -- XXII. Space and Geometry from the Point of View of Physical Enquiry -- XXIII. Physiological Time in Contrast with Metrical Time -- XXIV. Space and Time Physically Considered -- XXV. Sense and Value of the Laws of Nature -- Index of Names

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