 The question of the relationship between basic and non-basic entities features prominently in Russell’s thought. The method of logical construction (see section  4.3.1)  is his answer to this question. The two other traditional neutral monists—Mach and James—can arguably be characterized as reductionists (for an attempt to develop this claim a little further, see the supplement  Reducing Mind and Matter to Neutral Entities).  The contemporary discussion of this question is most vigorously addressed by various philosophers in the Russellian monist camp (see section  5.5).  There is considerable agreement that the basic neutral entities are related to the non-basic, non-neutral entities by way of the grounding relation. But many questions remain about the precise nature of the relata of the relevant grounding relations (see section  5.5).