 If this is so, then the Stoics’ position would be somewhat akin to externalist theories of knowledge or justification. Externalists insist that an agent might know a proposition or be justified in believing a proposition even when, nonetheless, the evidence for that belief is not subjectively available to the person. So, on one early externalist theory of knowledge, it was suggested that an agent might know a certain sort of proposition (e.g. that there is a fireplace here) if their belief that there is a fireplace here was caused by a reliable causal process (e.g. a normal visual system) – and not, e.g., by the interventions of wicked scientists fiddling with the subject’s brain. Annas (1990) explores the possibilities for reading the Stoic view as a proto-externalist one. Perin (2005) considers the limitations of this reading.