This book is written for those who approach philosophy for the first time (and one could add for those who do not think that philosophy is of much importance). The aim is to show that philosophy matters. The idea is that we must take philosophy seriously because we cannot avoid in everyday life or in the sciences but to build our reasoning on preconceived philosophical presuppositions and these, philosophy can show, could and sometimes should be of different sorts.

Trigg has chosen to concentrate on the problem of the nature of the world and how we obtain knowledge of it, and on what role science and reason play in this quest. As a result many important philosophical issues are only superficially dealt with, or not addressed at all. But I do not consider this as a problem. After all, the book is not intended to be an introduction to philosophy in the traditional sense, but a book that shows that philosophy is of great importance. Trigg even believes that philosophy should regain its place at the heart of intellectual life (142). We should certainly not – like some contemporary philosophers seem tempted to do – remain content with a merely scientific understanding of the structure of the world and with our ability to form beliefs about it and attain knowledge of it. Hence, questioning scientism (in the form of naturalism, materialism or physicalism) is a main theme in the book.

This means that Trigg wants to argue against the idea that philosophy is only the servant of the sciences, clarifying and systematizing their methods (14, 56). It could not on its own discover anything or understand anything. This scientistic understanding of philosophy naturally follows if one accepts that the methods of science alone can give us knowledge about reality. Instead, Trigg argues that we should see philosophy as an independent source of knowledge or as an alternative method of investigation. Even though it is not an empirical discipline, he thinks that philosophy can still be concerned with truth. On this issue, however, Trigg offers merely negative arguments. It would have strengthened his case if he had also tried to provide instances of what could count as philosophical knowledge or more broadly non-scientific knowledge.

Just as Trigg criticizes forms of scientism that flourish among many contemporary philosophers and scientists, he perceives severe difficulties with the other extreme: postmodernism in its relativist mode. Philosophy can ‘be seduced by the postmodernist attacks on the possibility of reason’ and happen to accept that human reason is always historically situated lacking any universal scope (56). Against relativism of this form Trigg argues that truth is the indispensable presupposition of all thought and language; otherwise anything goes. Communication presupposes a shared and stable world, which opens up the possibility for a common human rationality. ‘The minute we see that our society’s ways are not the only ones, and that other judgements about truth are possible, we are detaching ourselves from the thought-forms of a particular society. We are beginning to see our reasoning in ways that are not dictated by our social context’ (70). Thus, the inconsistency of relativism is that it has to use a rationality which is detached from context in order to show us how reason must always be rooted in its context.

Relativism fails to take the function and capacity of reason seriously, but this is, Trigg thinks, a problem that also haunts scientism or materialism (78–86). This is the case because the content of belief is made irrelevant by materialist evolutionary explanation. Beliefs are only relevant in so far as they lead us to do things that promote the spreading of our genes in the subsequent generations. This means that a materialist interpretation of the neo-Darwinian explanation cannot discriminate between different ideas or beliefs which have similar effects. But if this is so, how can we know that evolutionary theory is true and that the explanation of our beliefs and reason in terms of genetic fitness is correct? The difficulty is that the theory, if true and used as an all-sufficient explanation, may not be consistently argued for in a rational manner.

Indeed Trigg’s central thesis is that

More could and should of course be said about these arguments and possible counter-arguments than Trigg does. Nevertheless, I think that the book succeeds in showing that philosophy matters because what we think about scientism (or materialism) and relativism really matters. Some of the arguments that Trigg gives are also worth considering in much more detail than the form and aim of this book allows.