A nurse in an acute mental health facility is teaching a client about the potential adverse effects of transcranial magnetic stimulation. The nurse tells the client that he might feel lightheaded, but that it should not affect his memory. The nurse is demonstrating which of the following ethical principles?

Veracity is the ethical principle of truthfulness — the obligation to tell the truth and provide accurate, complete information to clients. When the nurse truthfully informs the client that transcranial magnetic stimulation may cause lightheadedness but will not affect memory, the nurse is providing honest, accurate information about both the side effects and a common misconception about the procedure. This directly exemplifies veracity. Fidelity refers to keeping promises and being loyal to the commitments made to clients, which is not the primary principle being demonstrated in this teaching scenario. Beneficence means acting in the client's best interest and doing good, which is a broader concept not specifically illustrated by the act of providing truthful information. Autonomy is the principle of respecting the client's right to make independent decisions; while truthful teaching supports autonomous decision-making, the nurse's act here is specifically about honesty rather than supporting decision-making capacity itself. The defining feature of this interaction is the nurse's commitment to giving the client accurate and honest information about both an expected adverse effect and a reassuring clarification, which is the hallmark of veracity.