The several long-confused, and now simply confusing, usages of the word ‘amateur’ are discussed and, using the chromatographic analogy of Robert Owen's four-sided Silent Monitor, four different meanings of the word are analysed and colour monitored. These include the ‘amateur’ as (a) enthusiast, (b) unpaid, (c) unqualified or (d) useless. The first use must apply to almost all geologists and so is hardly a useful one, while the others are so capable of misapplication that their uses should be considered carefully or the word avoided. The author much prefers the more neutral term ‘outsider’ and tries to point out that such people can have great advantages which should be recognized. The contents of the present volume certainly give grounds for realizing the often significant contributions made by such geologists, and they should encourage us to stop holding any idea that the ‘amateur’ is necessarily ‘second rate’ in future.