PAGE 



VI CONTENTS. 



CHAPTER XXVIII. 

 Necessaey Truths and the Effects of Experience, . 617 



Programme of the chapter, 617. Elementary feelings are 

 innate, 618. The question refers to their combinations, 619. 

 What is meant by 'experience,' 620. Spencer on ancestral ex- 

 perience, 620. Two ways in which new cerebral structure arises : 

 the 'back-door ' and the ' front-door' way, 625. The genesis of 

 the elementary mental categories, 631. The genesis of the 

 natural sciences, 633. Scientific conceptions arise as accidental 

 variations, 636. The genesis of the pure sciences, 641. Series of 

 evenly increasing terms, 644. The principle of mediate compari- 

 son, 645. That of skipped intermediaries, 646. Classification, 

 646. Predication, 647. Formal logic, 648. Mathematical 

 propositions, 652. Arithmetic, 653. Geometry, 656. Our doc- 

 trine is the same as Locke'.s, 661. Relations of ideas v. couplings 

 of things, 663. The natural sciences are inward ideal schemes 

 with which the order of nature proves congruent, 666. Meta- 

 physical principles are properly only postulates, 669. Esthetic 

 and moral principles are quite incongruent with the order of 

 nature, 672. Summary of what precedes, 675. The origin of 

 instincts, 678. Insufficiency of proof for the transmission to the 

 next generation of acquired habits, 681. Weismaun's views, 683. 

 Conclusion, 688. 



