It is well known that cognitive fluency affects various attitudes. We demonstrated that a subjective feeling of fluency, induced by repeated exposure to handwritten words, increases the acceptance of persuasive messages. Participants were repeatedly exposed to a set of handwritten words written in Japanese. In a subsequent test phase, they were required to rate the handwritten messages. The results showed that when the personal relevance of the messages was low, repeated exposure facilitated acceptance of messages written by the same person who had written the previously exposed words. This observation implies that we might make irrational decisions according to the ease with which the message can be processed, rather than according to the validity of message content.