Whitehead describes causal efficacy as "the experience dominating the primitive living organisms, which have a sense for the fate from which they have emerged, and the fate towards which they go." It is, in other words, the sense of causal relations between entities, a feeling of being influenced and affected by the surrounding environment, unmediated by the senses. Presentational immediacy, on the other hand, is what is usually referred to as <answer>"pure sense perception", unmediated by any causal or symbolic interpretation, even unconscious interpretation</answer>. In other words, it is pure appearance, which may or may not be delusive (e.g. mistaking an image in a mirror for "the real thing").
How does Whitehead define presentational immediacy?
"pure sense perception", unmediated by any causal or symbolic interpretation, even unconscious interpretation